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 <net/if.h>
17 #include <sys/mount.h>
18 #include <sys/resource.h>
19 #include <sys/stat.h>
20 #include <sys/vfs.h>
21
22 #include <linux/filter.h>
23 #include <linux/limits.h>
24 #include <linux/magic.h>
25 #include <linux/unistd.h>
26
27 #include <bpf/bpf.h>
28 #include <bpf/hashmap.h>
29 #include <bpf/libbpf.h> /* libbpf_num_possible_cpus */
30 #include <bpf/btf.h>
31
32 #include "main.h"
33
34 #ifndef BPF_FS_MAGIC
35 #define BPF_FS_MAGIC 0xcafe4a11
36 #endif
37
p_err(const char * fmt,...)38 void p_err(const char *fmt, ...)
39 {
40 va_list ap;
41
42 va_start(ap, fmt);
43 if (json_output) {
44 jsonw_start_object(json_wtr);
45 jsonw_name(json_wtr, "error");
46 jsonw_vprintf_enquote(json_wtr, fmt, ap);
47 jsonw_end_object(json_wtr);
48 } else {
49 fprintf(stderr, "Error: ");
50 vfprintf(stderr, fmt, ap);
51 fprintf(stderr, "\n");
52 }
53 va_end(ap);
54 }
55
p_info(const char * fmt,...)56 void p_info(const char *fmt, ...)
57 {
58 va_list ap;
59
60 if (json_output)
61 return;
62
63 va_start(ap, fmt);
64 vfprintf(stderr, fmt, ap);
65 fprintf(stderr, "\n");
66 va_end(ap);
67 }
68
is_bpffs(char * path)69 static bool is_bpffs(char *path)
70 {
71 struct statfs st_fs;
72
73 if (statfs(path, &st_fs) < 0)
74 return false;
75
76 return (unsigned long)st_fs.f_type == BPF_FS_MAGIC;
77 }
78
79 /* Probe whether kernel switched from memlock-based (RLIMIT_MEMLOCK) to
80 * memcg-based memory accounting for BPF maps and programs. This was done in
81 * commit 97306be45fbe ("Merge branch 'switch to memcg-based memory
82 * accounting'"), in Linux 5.11.
83 *
84 * Libbpf also offers to probe for memcg-based accounting vs rlimit, but does
85 * so by checking for the availability of a given BPF helper and this has
86 * failed on some kernels with backports in the past, see commit 6b4384ff1088
87 * ("Revert "bpftool: Use libbpf 1.0 API mode instead of RLIMIT_MEMLOCK"").
88 * Instead, we can probe by lowering the process-based rlimit to 0, trying to
89 * load a BPF object, and resetting the rlimit. If the load succeeds then
90 * memcg-based accounting is supported.
91 *
92 * This would be too dangerous to do in the library, because multithreaded
93 * applications might attempt to load items while the rlimit is at 0. Given
94 * that bpftool is single-threaded, this is fine to do here.
95 */
known_to_need_rlimit(void)96 static bool known_to_need_rlimit(void)
97 {
98 struct rlimit rlim_init, rlim_cur_zero = {};
99 struct bpf_insn insns[] = {
100 BPF_MOV64_IMM(BPF_REG_0, 0),
101 BPF_EXIT_INSN(),
102 };
103 size_t insn_cnt = ARRAY_SIZE(insns);
104 union bpf_attr attr;
105 int prog_fd, err;
106
107 memset(&attr, 0, sizeof(attr));
108 attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER;
109 attr.insns = ptr_to_u64(insns);
110 attr.insn_cnt = insn_cnt;
111 attr.license = ptr_to_u64("GPL");
112
113 if (getrlimit(RLIMIT_MEMLOCK, &rlim_init))
114 return false;
115
116 /* Drop the soft limit to zero. We maintain the hard limit to its
117 * current value, because lowering it would be a permanent operation
118 * for unprivileged users.
119 */
120 rlim_cur_zero.rlim_max = rlim_init.rlim_max;
121 if (setrlimit(RLIMIT_MEMLOCK, &rlim_cur_zero))
122 return false;
123
124 /* Do not use bpf_prog_load() from libbpf here, because it calls
125 * bump_rlimit_memlock(), interfering with the current probe.
126 */
127 prog_fd = syscall(__NR_bpf, BPF_PROG_LOAD, &attr, sizeof(attr));
128 err = errno;
129
130 /* reset soft rlimit to its initial value */
131 setrlimit(RLIMIT_MEMLOCK, &rlim_init);
132
133 if (prog_fd < 0)
134 return err == EPERM;
135
136 close(prog_fd);
137 return false;
138 }
139
set_max_rlimit(void)140 void set_max_rlimit(void)
141 {
142 struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
143
144 if (known_to_need_rlimit())
145 setrlimit(RLIMIT_MEMLOCK, &rinf);
146 }
147
148 static int
mnt_fs(const char * target,const char * type,char * buff,size_t bufflen)149 mnt_fs(const char *target, const char *type, char *buff, size_t bufflen)
150 {
151 bool bind_done = false;
152
153 while (mount("", target, "none", MS_PRIVATE | MS_REC, NULL)) {
154 if (errno != EINVAL || bind_done) {
155 snprintf(buff, bufflen,
156 "mount --make-private %s failed: %s",
157 target, strerror(errno));
158 return -1;
159 }
160
161 if (mount(target, target, "none", MS_BIND, NULL)) {
162 snprintf(buff, bufflen,
163 "mount --bind %s %s failed: %s",
164 target, target, strerror(errno));
165 return -1;
166 }
167
168 bind_done = true;
169 }
170
171 if (mount(type, target, type, 0, "mode=0700")) {
172 snprintf(buff, bufflen, "mount -t %s %s %s failed: %s",
173 type, type, target, strerror(errno));
174 return -1;
175 }
176
177 return 0;
178 }
179
mount_tracefs(const char * target)180 int mount_tracefs(const char *target)
181 {
182 char err_str[ERR_MAX_LEN];
183 int err;
184
185 err = mnt_fs(target, "tracefs", err_str, ERR_MAX_LEN);
186 if (err) {
187 err_str[ERR_MAX_LEN - 1] = '\0';
188 p_err("can't mount tracefs: %s", err_str);
189 }
190
191 return err;
192 }
193
open_obj_pinned(const char * path,bool quiet)194 int open_obj_pinned(const char *path, bool quiet)
195 {
196 char *pname;
197 int fd = -1;
198
199 pname = strdup(path);
200 if (!pname) {
201 if (!quiet)
202 p_err("mem alloc failed");
203 goto out_ret;
204 }
205
206 fd = bpf_obj_get(pname);
207 if (fd < 0) {
208 if (!quiet)
209 p_err("bpf obj get (%s): %s", pname,
210 errno == EACCES && !is_bpffs(dirname(pname)) ?
211 "directory not in bpf file system (bpffs)" :
212 strerror(errno));
213 goto out_free;
214 }
215
216 out_free:
217 free(pname);
218 out_ret:
219 return fd;
220 }
221
open_obj_pinned_any(const char * path,enum bpf_obj_type exp_type)222 int open_obj_pinned_any(const char *path, enum bpf_obj_type exp_type)
223 {
224 enum bpf_obj_type type;
225 int fd;
226
227 fd = open_obj_pinned(path, false);
228 if (fd < 0)
229 return -1;
230
231 type = get_fd_type(fd);
232 if (type < 0) {
233 close(fd);
234 return type;
235 }
236 if (type != exp_type) {
237 p_err("incorrect object type: %s", get_fd_type_name(type));
238 close(fd);
239 return -1;
240 }
241
242 return fd;
243 }
244
mount_bpffs_for_pin(const char * name)245 int mount_bpffs_for_pin(const char *name)
246 {
247 char err_str[ERR_MAX_LEN];
248 char *file;
249 char *dir;
250 int err = 0;
251
252 file = malloc(strlen(name) + 1);
253 if (!file) {
254 p_err("mem alloc failed");
255 return -1;
256 }
257
258 strcpy(file, name);
259 dir = dirname(file);
260
261 if (is_bpffs(dir))
262 /* nothing to do if already mounted */
263 goto out_free;
264
265 if (block_mount) {
266 p_err("no BPF file system found, not mounting it due to --nomount option");
267 err = -1;
268 goto out_free;
269 }
270
271 err = mnt_fs(dir, "bpf", err_str, ERR_MAX_LEN);
272 if (err) {
273 err_str[ERR_MAX_LEN - 1] = '\0';
274 p_err("can't mount BPF file system to pin the object (%s): %s",
275 name, err_str);
276 }
277
278 out_free:
279 free(file);
280 return err;
281 }
282
do_pin_fd(int fd,const char * name)283 int do_pin_fd(int fd, const char *name)
284 {
285 int err;
286
287 err = mount_bpffs_for_pin(name);
288 if (err)
289 return err;
290
291 err = bpf_obj_pin(fd, name);
292 if (err)
293 p_err("can't pin the object (%s): %s", name, strerror(errno));
294
295 return err;
296 }
297
do_pin_any(int argc,char ** argv,int (* get_fd)(int *,char ***))298 int do_pin_any(int argc, char **argv, int (*get_fd)(int *, char ***))
299 {
300 int err;
301 int fd;
302
303 if (!REQ_ARGS(3))
304 return -EINVAL;
305
306 fd = get_fd(&argc, &argv);
307 if (fd < 0)
308 return fd;
309
310 err = do_pin_fd(fd, *argv);
311
312 close(fd);
313 return err;
314 }
315
get_fd_type_name(enum bpf_obj_type type)316 const char *get_fd_type_name(enum bpf_obj_type type)
317 {
318 static const char * const names[] = {
319 [BPF_OBJ_UNKNOWN] = "unknown",
320 [BPF_OBJ_PROG] = "prog",
321 [BPF_OBJ_MAP] = "map",
322 [BPF_OBJ_LINK] = "link",
323 };
324
325 if (type < 0 || type >= ARRAY_SIZE(names) || !names[type])
326 return names[BPF_OBJ_UNKNOWN];
327
328 return names[type];
329 }
330
get_prog_full_name(const struct bpf_prog_info * prog_info,int prog_fd,char * name_buff,size_t buff_len)331 void get_prog_full_name(const struct bpf_prog_info *prog_info, int prog_fd,
332 char *name_buff, size_t buff_len)
333 {
334 const char *prog_name = prog_info->name;
335 const struct btf_type *func_type;
336 const struct bpf_func_info finfo = {};
337 struct bpf_prog_info info = {};
338 __u32 info_len = sizeof(info);
339 struct btf *prog_btf = NULL;
340
341 if (buff_len <= BPF_OBJ_NAME_LEN ||
342 strlen(prog_info->name) < BPF_OBJ_NAME_LEN - 1)
343 goto copy_name;
344
345 if (!prog_info->btf_id || prog_info->nr_func_info == 0)
346 goto copy_name;
347
348 info.nr_func_info = 1;
349 info.func_info_rec_size = prog_info->func_info_rec_size;
350 if (info.func_info_rec_size > sizeof(finfo))
351 info.func_info_rec_size = sizeof(finfo);
352 info.func_info = ptr_to_u64(&finfo);
353
354 if (bpf_obj_get_info_by_fd(prog_fd, &info, &info_len))
355 goto copy_name;
356
357 prog_btf = btf__load_from_kernel_by_id(info.btf_id);
358 if (!prog_btf)
359 goto copy_name;
360
361 func_type = btf__type_by_id(prog_btf, finfo.type_id);
362 if (!func_type || !btf_is_func(func_type))
363 goto copy_name;
364
365 prog_name = btf__name_by_offset(prog_btf, func_type->name_off);
366
367 copy_name:
368 snprintf(name_buff, buff_len, "%s", prog_name);
369
370 if (prog_btf)
371 btf__free(prog_btf);
372 }
373
get_fd_type(int fd)374 int get_fd_type(int fd)
375 {
376 char path[PATH_MAX];
377 char buf[512];
378 ssize_t n;
379
380 snprintf(path, sizeof(path), "/proc/self/fd/%d", fd);
381
382 n = readlink(path, buf, sizeof(buf));
383 if (n < 0) {
384 p_err("can't read link type: %s", strerror(errno));
385 return -1;
386 }
387 if (n == sizeof(path)) {
388 p_err("can't read link type: path too long!");
389 return -1;
390 }
391
392 if (strstr(buf, "bpf-map"))
393 return BPF_OBJ_MAP;
394 else if (strstr(buf, "bpf-prog"))
395 return BPF_OBJ_PROG;
396 else if (strstr(buf, "bpf-link"))
397 return BPF_OBJ_LINK;
398
399 return BPF_OBJ_UNKNOWN;
400 }
401
get_fdinfo(int fd,const char * key)402 char *get_fdinfo(int fd, const char *key)
403 {
404 char path[PATH_MAX];
405 char *line = NULL;
406 size_t line_n = 0;
407 ssize_t n;
408 FILE *fdi;
409
410 snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
411
412 fdi = fopen(path, "r");
413 if (!fdi)
414 return NULL;
415
416 while ((n = getline(&line, &line_n, fdi)) > 0) {
417 char *value;
418 int len;
419
420 if (!strstr(line, key))
421 continue;
422
423 fclose(fdi);
424
425 value = strchr(line, '\t');
426 if (!value || !value[1]) {
427 free(line);
428 return NULL;
429 }
430 value++;
431
432 len = strlen(value);
433 memmove(line, value, len);
434 line[len - 1] = '\0';
435
436 return line;
437 }
438
439 free(line);
440 fclose(fdi);
441 return NULL;
442 }
443
print_data_json(uint8_t * data,size_t len)444 void print_data_json(uint8_t *data, size_t len)
445 {
446 unsigned int i;
447
448 jsonw_start_array(json_wtr);
449 for (i = 0; i < len; i++)
450 jsonw_printf(json_wtr, "%d", data[i]);
451 jsonw_end_array(json_wtr);
452 }
453
print_hex_data_json(uint8_t * data,size_t len)454 void print_hex_data_json(uint8_t *data, size_t len)
455 {
456 unsigned int i;
457
458 jsonw_start_array(json_wtr);
459 for (i = 0; i < len; i++)
460 jsonw_printf(json_wtr, "\"0x%02hhx\"", data[i]);
461 jsonw_end_array(json_wtr);
462 }
463
464 /* extra params for nftw cb */
465 static struct hashmap *build_fn_table;
466 static enum bpf_obj_type build_fn_type;
467
do_build_table_cb(const char * fpath,const struct stat * sb,int typeflag,struct FTW * ftwbuf)468 static int do_build_table_cb(const char *fpath, const struct stat *sb,
469 int typeflag, struct FTW *ftwbuf)
470 {
471 struct bpf_prog_info pinned_info;
472 __u32 len = sizeof(pinned_info);
473 enum bpf_obj_type objtype;
474 int fd, err = 0;
475 char *path;
476
477 if (typeflag != FTW_F)
478 goto out_ret;
479
480 fd = open_obj_pinned(fpath, true);
481 if (fd < 0)
482 goto out_ret;
483
484 objtype = get_fd_type(fd);
485 if (objtype != build_fn_type)
486 goto out_close;
487
488 memset(&pinned_info, 0, sizeof(pinned_info));
489 if (bpf_obj_get_info_by_fd(fd, &pinned_info, &len))
490 goto out_close;
491
492 path = strdup(fpath);
493 if (!path) {
494 err = -1;
495 goto out_close;
496 }
497
498 err = hashmap__append(build_fn_table, u32_as_hash_field(pinned_info.id), path);
499 if (err) {
500 p_err("failed to append entry to hashmap for ID %u, path '%s': %s",
501 pinned_info.id, path, strerror(errno));
502 free(path);
503 goto out_close;
504 }
505
506 out_close:
507 close(fd);
508 out_ret:
509 return err;
510 }
511
build_pinned_obj_table(struct hashmap * tab,enum bpf_obj_type type)512 int build_pinned_obj_table(struct hashmap *tab,
513 enum bpf_obj_type type)
514 {
515 struct mntent *mntent = NULL;
516 FILE *mntfile = NULL;
517 int flags = FTW_PHYS;
518 int nopenfd = 16;
519 int err = 0;
520
521 mntfile = setmntent("/proc/mounts", "r");
522 if (!mntfile)
523 return -1;
524
525 build_fn_table = tab;
526 build_fn_type = type;
527
528 while ((mntent = getmntent(mntfile))) {
529 char *path = mntent->mnt_dir;
530
531 if (strncmp(mntent->mnt_type, "bpf", 3) != 0)
532 continue;
533 err = nftw(path, do_build_table_cb, nopenfd, flags);
534 if (err)
535 break;
536 }
537 fclose(mntfile);
538 return err;
539 }
540
delete_pinned_obj_table(struct hashmap * map)541 void delete_pinned_obj_table(struct hashmap *map)
542 {
543 struct hashmap_entry *entry;
544 size_t bkt;
545
546 if (!map)
547 return;
548
549 hashmap__for_each_entry(map, entry, bkt)
550 free(entry->value);
551
552 hashmap__free(map);
553 }
554
get_page_size(void)555 unsigned int get_page_size(void)
556 {
557 static int result;
558
559 if (!result)
560 result = getpagesize();
561 return result;
562 }
563
get_possible_cpus(void)564 unsigned int get_possible_cpus(void)
565 {
566 int cpus = libbpf_num_possible_cpus();
567
568 if (cpus < 0) {
569 p_err("Can't get # of possible cpus: %s", strerror(-cpus));
570 exit(-1);
571 }
572 return cpus;
573 }
574
575 static char *
ifindex_to_name_ns(__u32 ifindex,__u32 ns_dev,__u32 ns_ino,char * buf)576 ifindex_to_name_ns(__u32 ifindex, __u32 ns_dev, __u32 ns_ino, char *buf)
577 {
578 struct stat st;
579 int err;
580
581 err = stat("/proc/self/ns/net", &st);
582 if (err) {
583 p_err("Can't stat /proc/self: %s", strerror(errno));
584 return NULL;
585 }
586
587 if (st.st_dev != ns_dev || st.st_ino != ns_ino)
588 return NULL;
589
590 return if_indextoname(ifindex, buf);
591 }
592
read_sysfs_hex_int(char * path)593 static int read_sysfs_hex_int(char *path)
594 {
595 char vendor_id_buf[8];
596 int len;
597 int fd;
598
599 fd = open(path, O_RDONLY);
600 if (fd < 0) {
601 p_err("Can't open %s: %s", path, strerror(errno));
602 return -1;
603 }
604
605 len = read(fd, vendor_id_buf, sizeof(vendor_id_buf));
606 close(fd);
607 if (len < 0) {
608 p_err("Can't read %s: %s", path, strerror(errno));
609 return -1;
610 }
611 if (len >= (int)sizeof(vendor_id_buf)) {
612 p_err("Value in %s too long", path);
613 return -1;
614 }
615
616 vendor_id_buf[len] = 0;
617
618 return strtol(vendor_id_buf, NULL, 0);
619 }
620
read_sysfs_netdev_hex_int(char * devname,const char * entry_name)621 static int read_sysfs_netdev_hex_int(char *devname, const char *entry_name)
622 {
623 char full_path[64];
624
625 snprintf(full_path, sizeof(full_path), "/sys/class/net/%s/device/%s",
626 devname, entry_name);
627
628 return read_sysfs_hex_int(full_path);
629 }
630
631 const char *
ifindex_to_bfd_params(__u32 ifindex,__u64 ns_dev,__u64 ns_ino,const char ** opt)632 ifindex_to_bfd_params(__u32 ifindex, __u64 ns_dev, __u64 ns_ino,
633 const char **opt)
634 {
635 char devname[IF_NAMESIZE];
636 int vendor_id;
637 int device_id;
638
639 if (!ifindex_to_name_ns(ifindex, ns_dev, ns_ino, devname)) {
640 p_err("Can't get net device name for ifindex %d: %s", ifindex,
641 strerror(errno));
642 return NULL;
643 }
644
645 vendor_id = read_sysfs_netdev_hex_int(devname, "vendor");
646 if (vendor_id < 0) {
647 p_err("Can't get device vendor id for %s", devname);
648 return NULL;
649 }
650
651 switch (vendor_id) {
652 case 0x19ee:
653 device_id = read_sysfs_netdev_hex_int(devname, "device");
654 if (device_id != 0x4000 &&
655 device_id != 0x6000 &&
656 device_id != 0x6003)
657 p_info("Unknown NFP device ID, assuming it is NFP-6xxx arch");
658 *opt = "ctx4";
659 return "NFP-6xxx";
660 default:
661 p_err("Can't get bfd arch name for device vendor id 0x%04x",
662 vendor_id);
663 return NULL;
664 }
665 }
666
print_dev_plain(__u32 ifindex,__u64 ns_dev,__u64 ns_inode)667 void print_dev_plain(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
668 {
669 char name[IF_NAMESIZE];
670
671 if (!ifindex)
672 return;
673
674 printf(" offloaded_to ");
675 if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
676 printf("%s", name);
677 else
678 printf("ifindex %u ns_dev %llu ns_ino %llu",
679 ifindex, ns_dev, ns_inode);
680 }
681
print_dev_json(__u32 ifindex,__u64 ns_dev,__u64 ns_inode)682 void print_dev_json(__u32 ifindex, __u64 ns_dev, __u64 ns_inode)
683 {
684 char name[IF_NAMESIZE];
685
686 if (!ifindex)
687 return;
688
689 jsonw_name(json_wtr, "dev");
690 jsonw_start_object(json_wtr);
691 jsonw_uint_field(json_wtr, "ifindex", ifindex);
692 jsonw_uint_field(json_wtr, "ns_dev", ns_dev);
693 jsonw_uint_field(json_wtr, "ns_inode", ns_inode);
694 if (ifindex_to_name_ns(ifindex, ns_dev, ns_inode, name))
695 jsonw_string_field(json_wtr, "ifname", name);
696 jsonw_end_object(json_wtr);
697 }
698
parse_u32_arg(int * argc,char *** argv,__u32 * val,const char * what)699 int parse_u32_arg(int *argc, char ***argv, __u32 *val, const char *what)
700 {
701 char *endptr;
702
703 NEXT_ARGP();
704
705 if (*val) {
706 p_err("%s already specified", what);
707 return -1;
708 }
709
710 *val = strtoul(**argv, &endptr, 0);
711 if (*endptr) {
712 p_err("can't parse %s as %s", **argv, what);
713 return -1;
714 }
715 NEXT_ARGP();
716
717 return 0;
718 }
719
720 int __printf(2, 0)
print_all_levels(__maybe_unused enum libbpf_print_level level,const char * format,va_list args)721 print_all_levels(__maybe_unused enum libbpf_print_level level,
722 const char *format, va_list args)
723 {
724 return vfprintf(stderr, format, args);
725 }
726
prog_fd_by_nametag(void * nametag,int ** fds,bool tag)727 static int prog_fd_by_nametag(void *nametag, int **fds, bool tag)
728 {
729 char prog_name[MAX_PROG_FULL_NAME];
730 unsigned int id = 0;
731 int fd, nb_fds = 0;
732 void *tmp;
733 int err;
734
735 while (true) {
736 struct bpf_prog_info info = {};
737 __u32 len = sizeof(info);
738
739 err = bpf_prog_get_next_id(id, &id);
740 if (err) {
741 if (errno != ENOENT) {
742 p_err("%s", strerror(errno));
743 goto err_close_fds;
744 }
745 return nb_fds;
746 }
747
748 fd = bpf_prog_get_fd_by_id(id);
749 if (fd < 0) {
750 p_err("can't get prog by id (%u): %s",
751 id, strerror(errno));
752 goto err_close_fds;
753 }
754
755 err = bpf_obj_get_info_by_fd(fd, &info, &len);
756 if (err) {
757 p_err("can't get prog info (%u): %s",
758 id, strerror(errno));
759 goto err_close_fd;
760 }
761
762 if (tag && memcmp(nametag, info.tag, BPF_TAG_SIZE)) {
763 close(fd);
764 continue;
765 }
766
767 if (!tag) {
768 get_prog_full_name(&info, fd, prog_name,
769 sizeof(prog_name));
770 if (strncmp(nametag, prog_name, sizeof(prog_name))) {
771 close(fd);
772 continue;
773 }
774 }
775
776 if (nb_fds > 0) {
777 tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
778 if (!tmp) {
779 p_err("failed to realloc");
780 goto err_close_fd;
781 }
782 *fds = tmp;
783 }
784 (*fds)[nb_fds++] = fd;
785 }
786
787 err_close_fd:
788 close(fd);
789 err_close_fds:
790 while (--nb_fds >= 0)
791 close((*fds)[nb_fds]);
792 return -1;
793 }
794
prog_parse_fds(int * argc,char *** argv,int ** fds)795 int prog_parse_fds(int *argc, char ***argv, int **fds)
796 {
797 if (is_prefix(**argv, "id")) {
798 unsigned int id;
799 char *endptr;
800
801 NEXT_ARGP();
802
803 id = strtoul(**argv, &endptr, 0);
804 if (*endptr) {
805 p_err("can't parse %s as ID", **argv);
806 return -1;
807 }
808 NEXT_ARGP();
809
810 (*fds)[0] = bpf_prog_get_fd_by_id(id);
811 if ((*fds)[0] < 0) {
812 p_err("get by id (%u): %s", id, strerror(errno));
813 return -1;
814 }
815 return 1;
816 } else if (is_prefix(**argv, "tag")) {
817 unsigned char tag[BPF_TAG_SIZE];
818
819 NEXT_ARGP();
820
821 if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
822 tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
823 != BPF_TAG_SIZE) {
824 p_err("can't parse tag");
825 return -1;
826 }
827 NEXT_ARGP();
828
829 return prog_fd_by_nametag(tag, fds, true);
830 } else if (is_prefix(**argv, "name")) {
831 char *name;
832
833 NEXT_ARGP();
834
835 name = **argv;
836 if (strlen(name) > MAX_PROG_FULL_NAME - 1) {
837 p_err("can't parse name");
838 return -1;
839 }
840 NEXT_ARGP();
841
842 return prog_fd_by_nametag(name, fds, false);
843 } else if (is_prefix(**argv, "pinned")) {
844 char *path;
845
846 NEXT_ARGP();
847
848 path = **argv;
849 NEXT_ARGP();
850
851 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_PROG);
852 if ((*fds)[0] < 0)
853 return -1;
854 return 1;
855 }
856
857 p_err("expected 'id', 'tag', 'name' or 'pinned', got: '%s'?", **argv);
858 return -1;
859 }
860
prog_parse_fd(int * argc,char *** argv)861 int prog_parse_fd(int *argc, char ***argv)
862 {
863 int *fds = NULL;
864 int nb_fds, fd;
865
866 fds = malloc(sizeof(int));
867 if (!fds) {
868 p_err("mem alloc failed");
869 return -1;
870 }
871 nb_fds = prog_parse_fds(argc, argv, &fds);
872 if (nb_fds != 1) {
873 if (nb_fds > 1) {
874 p_err("several programs match this handle");
875 while (nb_fds--)
876 close(fds[nb_fds]);
877 }
878 fd = -1;
879 goto exit_free;
880 }
881
882 fd = fds[0];
883 exit_free:
884 free(fds);
885 return fd;
886 }
887
map_fd_by_name(char * name,int ** fds)888 static int map_fd_by_name(char *name, int **fds)
889 {
890 unsigned int id = 0;
891 int fd, nb_fds = 0;
892 void *tmp;
893 int err;
894
895 while (true) {
896 struct bpf_map_info info = {};
897 __u32 len = sizeof(info);
898
899 err = bpf_map_get_next_id(id, &id);
900 if (err) {
901 if (errno != ENOENT) {
902 p_err("%s", strerror(errno));
903 goto err_close_fds;
904 }
905 return nb_fds;
906 }
907
908 fd = bpf_map_get_fd_by_id(id);
909 if (fd < 0) {
910 p_err("can't get map by id (%u): %s",
911 id, strerror(errno));
912 goto err_close_fds;
913 }
914
915 err = bpf_obj_get_info_by_fd(fd, &info, &len);
916 if (err) {
917 p_err("can't get map info (%u): %s",
918 id, strerror(errno));
919 goto err_close_fd;
920 }
921
922 if (strncmp(name, info.name, BPF_OBJ_NAME_LEN)) {
923 close(fd);
924 continue;
925 }
926
927 if (nb_fds > 0) {
928 tmp = realloc(*fds, (nb_fds + 1) * sizeof(int));
929 if (!tmp) {
930 p_err("failed to realloc");
931 goto err_close_fd;
932 }
933 *fds = tmp;
934 }
935 (*fds)[nb_fds++] = fd;
936 }
937
938 err_close_fd:
939 close(fd);
940 err_close_fds:
941 while (--nb_fds >= 0)
942 close((*fds)[nb_fds]);
943 return -1;
944 }
945
map_parse_fds(int * argc,char *** argv,int ** fds)946 int map_parse_fds(int *argc, char ***argv, int **fds)
947 {
948 if (is_prefix(**argv, "id")) {
949 unsigned int id;
950 char *endptr;
951
952 NEXT_ARGP();
953
954 id = strtoul(**argv, &endptr, 0);
955 if (*endptr) {
956 p_err("can't parse %s as ID", **argv);
957 return -1;
958 }
959 NEXT_ARGP();
960
961 (*fds)[0] = bpf_map_get_fd_by_id(id);
962 if ((*fds)[0] < 0) {
963 p_err("get map by id (%u): %s", id, strerror(errno));
964 return -1;
965 }
966 return 1;
967 } else if (is_prefix(**argv, "name")) {
968 char *name;
969
970 NEXT_ARGP();
971
972 name = **argv;
973 if (strlen(name) > BPF_OBJ_NAME_LEN - 1) {
974 p_err("can't parse name");
975 return -1;
976 }
977 NEXT_ARGP();
978
979 return map_fd_by_name(name, fds);
980 } else if (is_prefix(**argv, "pinned")) {
981 char *path;
982
983 NEXT_ARGP();
984
985 path = **argv;
986 NEXT_ARGP();
987
988 (*fds)[0] = open_obj_pinned_any(path, BPF_OBJ_MAP);
989 if ((*fds)[0] < 0)
990 return -1;
991 return 1;
992 }
993
994 p_err("expected 'id', 'name' or 'pinned', got: '%s'?", **argv);
995 return -1;
996 }
997
map_parse_fd(int * argc,char *** argv)998 int map_parse_fd(int *argc, char ***argv)
999 {
1000 int *fds = NULL;
1001 int nb_fds, fd;
1002
1003 fds = malloc(sizeof(int));
1004 if (!fds) {
1005 p_err("mem alloc failed");
1006 return -1;
1007 }
1008 nb_fds = map_parse_fds(argc, argv, &fds);
1009 if (nb_fds != 1) {
1010 if (nb_fds > 1) {
1011 p_err("several maps match this handle");
1012 while (nb_fds--)
1013 close(fds[nb_fds]);
1014 }
1015 fd = -1;
1016 goto exit_free;
1017 }
1018
1019 fd = fds[0];
1020 exit_free:
1021 free(fds);
1022 return fd;
1023 }
1024
map_parse_fd_and_info(int * argc,char *** argv,void * info,__u32 * info_len)1025 int map_parse_fd_and_info(int *argc, char ***argv, void *info, __u32 *info_len)
1026 {
1027 int err;
1028 int fd;
1029
1030 fd = map_parse_fd(argc, argv);
1031 if (fd < 0)
1032 return -1;
1033
1034 err = bpf_obj_get_info_by_fd(fd, info, info_len);
1035 if (err) {
1036 p_err("can't get map info: %s", strerror(errno));
1037 close(fd);
1038 return err;
1039 }
1040
1041 return fd;
1042 }
1043
hash_fn_for_key_as_id(const void * key,void * ctx)1044 size_t hash_fn_for_key_as_id(const void *key, void *ctx)
1045 {
1046 return (size_t)key;
1047 }
1048
equal_fn_for_key_as_id(const void * k1,const void * k2,void * ctx)1049 bool equal_fn_for_key_as_id(const void *k1, const void *k2, void *ctx)
1050 {
1051 return k1 == k2;
1052 }
1053
bpf_attach_type_input_str(enum bpf_attach_type t)1054 const char *bpf_attach_type_input_str(enum bpf_attach_type t)
1055 {
1056 switch (t) {
1057 case BPF_CGROUP_INET_INGRESS: return "ingress";
1058 case BPF_CGROUP_INET_EGRESS: return "egress";
1059 case BPF_CGROUP_INET_SOCK_CREATE: return "sock_create";
1060 case BPF_CGROUP_INET_SOCK_RELEASE: return "sock_release";
1061 case BPF_CGROUP_SOCK_OPS: return "sock_ops";
1062 case BPF_CGROUP_DEVICE: return "device";
1063 case BPF_CGROUP_INET4_BIND: return "bind4";
1064 case BPF_CGROUP_INET6_BIND: return "bind6";
1065 case BPF_CGROUP_INET4_CONNECT: return "connect4";
1066 case BPF_CGROUP_INET6_CONNECT: return "connect6";
1067 case BPF_CGROUP_INET4_POST_BIND: return "post_bind4";
1068 case BPF_CGROUP_INET6_POST_BIND: return "post_bind6";
1069 case BPF_CGROUP_INET4_GETPEERNAME: return "getpeername4";
1070 case BPF_CGROUP_INET6_GETPEERNAME: return "getpeername6";
1071 case BPF_CGROUP_INET4_GETSOCKNAME: return "getsockname4";
1072 case BPF_CGROUP_INET6_GETSOCKNAME: return "getsockname6";
1073 case BPF_CGROUP_UDP4_SENDMSG: return "sendmsg4";
1074 case BPF_CGROUP_UDP6_SENDMSG: return "sendmsg6";
1075 case BPF_CGROUP_SYSCTL: return "sysctl";
1076 case BPF_CGROUP_UDP4_RECVMSG: return "recvmsg4";
1077 case BPF_CGROUP_UDP6_RECVMSG: return "recvmsg6";
1078 case BPF_CGROUP_GETSOCKOPT: return "getsockopt";
1079 case BPF_CGROUP_SETSOCKOPT: return "setsockopt";
1080 case BPF_TRACE_RAW_TP: return "raw_tp";
1081 case BPF_TRACE_FENTRY: return "fentry";
1082 case BPF_TRACE_FEXIT: return "fexit";
1083 case BPF_MODIFY_RETURN: return "mod_ret";
1084 case BPF_SK_REUSEPORT_SELECT: return "sk_skb_reuseport_select";
1085 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE: return "sk_skb_reuseport_select_or_migrate";
1086 default: return libbpf_bpf_attach_type_str(t);
1087 }
1088 }
1089