xref: /openbmc/linux/tools/bpf/bpftool/prog.c (revision c4c8f39a57bf5057fc51a848d42b7e348ecfa31d)
1 /*
2  * Copyright (C) 2017 Netronome Systems, Inc.
3  *
4  * This software is dual licensed under the GNU General License Version 2,
5  * June 1991 as shown in the file COPYING in the top-level directory of this
6  * source tree or the BSD 2-Clause License provided below.  You have the
7  * option to license this software under the complete terms of either license.
8  *
9  * The BSD 2-Clause License:
10  *
11  *     Redistribution and use in source and binary forms, with or
12  *     without modification, are permitted provided that the following
13  *     conditions are met:
14  *
15  *      1. Redistributions of source code must retain the above
16  *         copyright notice, this list of conditions and the following
17  *         disclaimer.
18  *
19  *      2. Redistributions in binary form must reproduce the above
20  *         copyright notice, this list of conditions and the following
21  *         disclaimer in the documentation and/or other materials
22  *         provided with the distribution.
23  *
24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
31  * SOFTWARE.
32  */
33 
34 /* Author: Jakub Kicinski <kubakici@wp.pl> */
35 
36 #include <errno.h>
37 #include <fcntl.h>
38 #include <stdarg.h>
39 #include <stdio.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <time.h>
43 #include <unistd.h>
44 #include <sys/types.h>
45 #include <sys/stat.h>
46 
47 #include <bpf.h>
48 #include <libbpf.h>
49 
50 #include "cfg.h"
51 #include "main.h"
52 #include "xlated_dumper.h"
53 
54 static const char * const prog_type_name[] = {
55 	[BPF_PROG_TYPE_UNSPEC]		= "unspec",
56 	[BPF_PROG_TYPE_SOCKET_FILTER]	= "socket_filter",
57 	[BPF_PROG_TYPE_KPROBE]		= "kprobe",
58 	[BPF_PROG_TYPE_SCHED_CLS]	= "sched_cls",
59 	[BPF_PROG_TYPE_SCHED_ACT]	= "sched_act",
60 	[BPF_PROG_TYPE_TRACEPOINT]	= "tracepoint",
61 	[BPF_PROG_TYPE_XDP]		= "xdp",
62 	[BPF_PROG_TYPE_PERF_EVENT]	= "perf_event",
63 	[BPF_PROG_TYPE_CGROUP_SKB]	= "cgroup_skb",
64 	[BPF_PROG_TYPE_CGROUP_SOCK]	= "cgroup_sock",
65 	[BPF_PROG_TYPE_LWT_IN]		= "lwt_in",
66 	[BPF_PROG_TYPE_LWT_OUT]		= "lwt_out",
67 	[BPF_PROG_TYPE_LWT_XMIT]	= "lwt_xmit",
68 	[BPF_PROG_TYPE_SOCK_OPS]	= "sock_ops",
69 	[BPF_PROG_TYPE_SK_SKB]		= "sk_skb",
70 	[BPF_PROG_TYPE_CGROUP_DEVICE]	= "cgroup_device",
71 	[BPF_PROG_TYPE_SK_MSG]		= "sk_msg",
72 	[BPF_PROG_TYPE_RAW_TRACEPOINT]	= "raw_tracepoint",
73 	[BPF_PROG_TYPE_CGROUP_SOCK_ADDR] = "cgroup_sock_addr",
74 };
75 
76 static void print_boot_time(__u64 nsecs, char *buf, unsigned int size)
77 {
78 	struct timespec real_time_ts, boot_time_ts;
79 	time_t wallclock_secs;
80 	struct tm load_tm;
81 
82 	buf[--size] = '\0';
83 
84 	if (clock_gettime(CLOCK_REALTIME, &real_time_ts) ||
85 	    clock_gettime(CLOCK_BOOTTIME, &boot_time_ts)) {
86 		perror("Can't read clocks");
87 		snprintf(buf, size, "%llu", nsecs / 1000000000);
88 		return;
89 	}
90 
91 	wallclock_secs = (real_time_ts.tv_sec - boot_time_ts.tv_sec) +
92 		nsecs / 1000000000;
93 
94 	if (!localtime_r(&wallclock_secs, &load_tm)) {
95 		snprintf(buf, size, "%llu", nsecs / 1000000000);
96 		return;
97 	}
98 
99 	if (json_output)
100 		strftime(buf, size, "%s", &load_tm);
101 	else
102 		strftime(buf, size, "%FT%T%z", &load_tm);
103 }
104 
105 static int prog_fd_by_tag(unsigned char *tag)
106 {
107 	struct bpf_prog_info info = {};
108 	__u32 len = sizeof(info);
109 	unsigned int id = 0;
110 	int err;
111 	int fd;
112 
113 	while (true) {
114 		err = bpf_prog_get_next_id(id, &id);
115 		if (err) {
116 			p_err("%s", strerror(errno));
117 			return -1;
118 		}
119 
120 		fd = bpf_prog_get_fd_by_id(id);
121 		if (fd < 0) {
122 			p_err("can't get prog by id (%u): %s",
123 			      id, strerror(errno));
124 			return -1;
125 		}
126 
127 		err = bpf_obj_get_info_by_fd(fd, &info, &len);
128 		if (err) {
129 			p_err("can't get prog info (%u): %s",
130 			      id, strerror(errno));
131 			close(fd);
132 			return -1;
133 		}
134 
135 		if (!memcmp(tag, info.tag, BPF_TAG_SIZE))
136 			return fd;
137 
138 		close(fd);
139 	}
140 }
141 
142 int prog_parse_fd(int *argc, char ***argv)
143 {
144 	int fd;
145 
146 	if (is_prefix(**argv, "id")) {
147 		unsigned int id;
148 		char *endptr;
149 
150 		NEXT_ARGP();
151 
152 		id = strtoul(**argv, &endptr, 0);
153 		if (*endptr) {
154 			p_err("can't parse %s as ID", **argv);
155 			return -1;
156 		}
157 		NEXT_ARGP();
158 
159 		fd = bpf_prog_get_fd_by_id(id);
160 		if (fd < 0)
161 			p_err("get by id (%u): %s", id, strerror(errno));
162 		return fd;
163 	} else if (is_prefix(**argv, "tag")) {
164 		unsigned char tag[BPF_TAG_SIZE];
165 
166 		NEXT_ARGP();
167 
168 		if (sscanf(**argv, BPF_TAG_FMT, tag, tag + 1, tag + 2,
169 			   tag + 3, tag + 4, tag + 5, tag + 6, tag + 7)
170 		    != BPF_TAG_SIZE) {
171 			p_err("can't parse tag");
172 			return -1;
173 		}
174 		NEXT_ARGP();
175 
176 		return prog_fd_by_tag(tag);
177 	} else if (is_prefix(**argv, "pinned")) {
178 		char *path;
179 
180 		NEXT_ARGP();
181 
182 		path = **argv;
183 		NEXT_ARGP();
184 
185 		return open_obj_pinned_any(path, BPF_OBJ_PROG);
186 	}
187 
188 	p_err("expected 'id', 'tag' or 'pinned', got: '%s'?", **argv);
189 	return -1;
190 }
191 
192 static void show_prog_maps(int fd, u32 num_maps)
193 {
194 	struct bpf_prog_info info = {};
195 	__u32 len = sizeof(info);
196 	__u32 map_ids[num_maps];
197 	unsigned int i;
198 	int err;
199 
200 	info.nr_map_ids = num_maps;
201 	info.map_ids = ptr_to_u64(map_ids);
202 
203 	err = bpf_obj_get_info_by_fd(fd, &info, &len);
204 	if (err || !info.nr_map_ids)
205 		return;
206 
207 	if (json_output) {
208 		jsonw_name(json_wtr, "map_ids");
209 		jsonw_start_array(json_wtr);
210 		for (i = 0; i < info.nr_map_ids; i++)
211 			jsonw_uint(json_wtr, map_ids[i]);
212 		jsonw_end_array(json_wtr);
213 	} else {
214 		printf("  map_ids ");
215 		for (i = 0; i < info.nr_map_ids; i++)
216 			printf("%u%s", map_ids[i],
217 			       i == info.nr_map_ids - 1 ? "" : ",");
218 	}
219 }
220 
221 static void print_prog_json(struct bpf_prog_info *info, int fd)
222 {
223 	char *memlock;
224 
225 	jsonw_start_object(json_wtr);
226 	jsonw_uint_field(json_wtr, "id", info->id);
227 	if (info->type < ARRAY_SIZE(prog_type_name))
228 		jsonw_string_field(json_wtr, "type",
229 				   prog_type_name[info->type]);
230 	else
231 		jsonw_uint_field(json_wtr, "type", info->type);
232 
233 	if (*info->name)
234 		jsonw_string_field(json_wtr, "name", info->name);
235 
236 	jsonw_name(json_wtr, "tag");
237 	jsonw_printf(json_wtr, "\"" BPF_TAG_FMT "\"",
238 		     info->tag[0], info->tag[1], info->tag[2], info->tag[3],
239 		     info->tag[4], info->tag[5], info->tag[6], info->tag[7]);
240 
241 	jsonw_bool_field(json_wtr, "gpl_compatible", info->gpl_compatible);
242 
243 	print_dev_json(info->ifindex, info->netns_dev, info->netns_ino);
244 
245 	if (info->load_time) {
246 		char buf[32];
247 
248 		print_boot_time(info->load_time, buf, sizeof(buf));
249 
250 		/* Piggy back on load_time, since 0 uid is a valid one */
251 		jsonw_name(json_wtr, "loaded_at");
252 		jsonw_printf(json_wtr, "%s", buf);
253 		jsonw_uint_field(json_wtr, "uid", info->created_by_uid);
254 	}
255 
256 	jsonw_uint_field(json_wtr, "bytes_xlated", info->xlated_prog_len);
257 
258 	if (info->jited_prog_len) {
259 		jsonw_bool_field(json_wtr, "jited", true);
260 		jsonw_uint_field(json_wtr, "bytes_jited", info->jited_prog_len);
261 	} else {
262 		jsonw_bool_field(json_wtr, "jited", false);
263 	}
264 
265 	memlock = get_fdinfo(fd, "memlock");
266 	if (memlock)
267 		jsonw_int_field(json_wtr, "bytes_memlock", atoi(memlock));
268 	free(memlock);
269 
270 	if (info->nr_map_ids)
271 		show_prog_maps(fd, info->nr_map_ids);
272 
273 	if (!hash_empty(prog_table.table)) {
274 		struct pinned_obj *obj;
275 
276 		jsonw_name(json_wtr, "pinned");
277 		jsonw_start_array(json_wtr);
278 		hash_for_each_possible(prog_table.table, obj, hash, info->id) {
279 			if (obj->id == info->id)
280 				jsonw_string(json_wtr, obj->path);
281 		}
282 		jsonw_end_array(json_wtr);
283 	}
284 
285 	jsonw_end_object(json_wtr);
286 }
287 
288 static void print_prog_plain(struct bpf_prog_info *info, int fd)
289 {
290 	char *memlock;
291 
292 	printf("%u: ", info->id);
293 	if (info->type < ARRAY_SIZE(prog_type_name))
294 		printf("%s  ", prog_type_name[info->type]);
295 	else
296 		printf("type %u  ", info->type);
297 
298 	if (*info->name)
299 		printf("name %s  ", info->name);
300 
301 	printf("tag ");
302 	fprint_hex(stdout, info->tag, BPF_TAG_SIZE, "");
303 	print_dev_plain(info->ifindex, info->netns_dev, info->netns_ino);
304 	printf("%s", info->gpl_compatible ? "  gpl" : "");
305 	printf("\n");
306 
307 	if (info->load_time) {
308 		char buf[32];
309 
310 		print_boot_time(info->load_time, buf, sizeof(buf));
311 
312 		/* Piggy back on load_time, since 0 uid is a valid one */
313 		printf("\tloaded_at %s  uid %u\n", buf, info->created_by_uid);
314 	}
315 
316 	printf("\txlated %uB", info->xlated_prog_len);
317 
318 	if (info->jited_prog_len)
319 		printf("  jited %uB", info->jited_prog_len);
320 	else
321 		printf("  not jited");
322 
323 	memlock = get_fdinfo(fd, "memlock");
324 	if (memlock)
325 		printf("  memlock %sB", memlock);
326 	free(memlock);
327 
328 	if (info->nr_map_ids)
329 		show_prog_maps(fd, info->nr_map_ids);
330 
331 	if (!hash_empty(prog_table.table)) {
332 		struct pinned_obj *obj;
333 
334 		printf("\n");
335 		hash_for_each_possible(prog_table.table, obj, hash, info->id) {
336 			if (obj->id == info->id)
337 				printf("\tpinned %s\n", obj->path);
338 		}
339 	}
340 
341 	printf("\n");
342 }
343 
344 static int show_prog(int fd)
345 {
346 	struct bpf_prog_info info = {};
347 	__u32 len = sizeof(info);
348 	int err;
349 
350 	err = bpf_obj_get_info_by_fd(fd, &info, &len);
351 	if (err) {
352 		p_err("can't get prog info: %s", strerror(errno));
353 		return -1;
354 	}
355 
356 	if (json_output)
357 		print_prog_json(&info, fd);
358 	else
359 		print_prog_plain(&info, fd);
360 
361 	return 0;
362 }
363 
364 static int do_show(int argc, char **argv)
365 {
366 	__u32 id = 0;
367 	int err;
368 	int fd;
369 
370 	if (show_pinned)
371 		build_pinned_obj_table(&prog_table, BPF_OBJ_PROG);
372 
373 	if (argc == 2) {
374 		fd = prog_parse_fd(&argc, &argv);
375 		if (fd < 0)
376 			return -1;
377 
378 		return show_prog(fd);
379 	}
380 
381 	if (argc)
382 		return BAD_ARG();
383 
384 	if (json_output)
385 		jsonw_start_array(json_wtr);
386 	while (true) {
387 		err = bpf_prog_get_next_id(id, &id);
388 		if (err) {
389 			if (errno == ENOENT) {
390 				err = 0;
391 				break;
392 			}
393 			p_err("can't get next program: %s%s", strerror(errno),
394 			      errno == EINVAL ? " -- kernel too old?" : "");
395 			err = -1;
396 			break;
397 		}
398 
399 		fd = bpf_prog_get_fd_by_id(id);
400 		if (fd < 0) {
401 			if (errno == ENOENT)
402 				continue;
403 			p_err("can't get prog by id (%u): %s",
404 			      id, strerror(errno));
405 			err = -1;
406 			break;
407 		}
408 
409 		err = show_prog(fd);
410 		close(fd);
411 		if (err)
412 			break;
413 	}
414 
415 	if (json_output)
416 		jsonw_end_array(json_wtr);
417 
418 	return err;
419 }
420 
421 static int do_dump(int argc, char **argv)
422 {
423 	struct bpf_prog_info info = {};
424 	struct dump_data dd = {};
425 	__u32 len = sizeof(info);
426 	unsigned int buf_size;
427 	char *filepath = NULL;
428 	bool opcodes = false;
429 	bool visual = false;
430 	unsigned char *buf;
431 	__u32 *member_len;
432 	__u64 *member_ptr;
433 	ssize_t n;
434 	int err;
435 	int fd;
436 
437 	if (is_prefix(*argv, "jited")) {
438 		member_len = &info.jited_prog_len;
439 		member_ptr = &info.jited_prog_insns;
440 	} else if (is_prefix(*argv, "xlated")) {
441 		member_len = &info.xlated_prog_len;
442 		member_ptr = &info.xlated_prog_insns;
443 	} else {
444 		p_err("expected 'xlated' or 'jited', got: %s", *argv);
445 		return -1;
446 	}
447 	NEXT_ARG();
448 
449 	if (argc < 2)
450 		usage();
451 
452 	fd = prog_parse_fd(&argc, &argv);
453 	if (fd < 0)
454 		return -1;
455 
456 	if (is_prefix(*argv, "file")) {
457 		NEXT_ARG();
458 		if (!argc) {
459 			p_err("expected file path");
460 			return -1;
461 		}
462 
463 		filepath = *argv;
464 		NEXT_ARG();
465 	} else if (is_prefix(*argv, "opcodes")) {
466 		opcodes = true;
467 		NEXT_ARG();
468 	} else if (is_prefix(*argv, "visual")) {
469 		visual = true;
470 		NEXT_ARG();
471 	}
472 
473 	if (argc) {
474 		usage();
475 		return -1;
476 	}
477 
478 	err = bpf_obj_get_info_by_fd(fd, &info, &len);
479 	if (err) {
480 		p_err("can't get prog info: %s", strerror(errno));
481 		return -1;
482 	}
483 
484 	if (!*member_len) {
485 		p_info("no instructions returned");
486 		close(fd);
487 		return 0;
488 	}
489 
490 	buf_size = *member_len;
491 
492 	buf = malloc(buf_size);
493 	if (!buf) {
494 		p_err("mem alloc failed");
495 		close(fd);
496 		return -1;
497 	}
498 
499 	memset(&info, 0, sizeof(info));
500 
501 	*member_ptr = ptr_to_u64(buf);
502 	*member_len = buf_size;
503 
504 	err = bpf_obj_get_info_by_fd(fd, &info, &len);
505 	close(fd);
506 	if (err) {
507 		p_err("can't get prog info: %s", strerror(errno));
508 		goto err_free;
509 	}
510 
511 	if (*member_len > buf_size) {
512 		p_err("too many instructions returned");
513 		goto err_free;
514 	}
515 
516 	if ((member_len == &info.jited_prog_len &&
517 	     info.jited_prog_insns == 0) ||
518 	    (member_len == &info.xlated_prog_len &&
519 	     info.xlated_prog_insns == 0)) {
520 		p_err("error retrieving insn dump: kernel.kptr_restrict set?");
521 		goto err_free;
522 	}
523 
524 	if (filepath) {
525 		fd = open(filepath, O_WRONLY | O_CREAT | O_TRUNC, 0600);
526 		if (fd < 0) {
527 			p_err("can't open file %s: %s", filepath,
528 			      strerror(errno));
529 			goto err_free;
530 		}
531 
532 		n = write(fd, buf, *member_len);
533 		close(fd);
534 		if (n != *member_len) {
535 			p_err("error writing output file: %s",
536 			      n < 0 ? strerror(errno) : "short write");
537 			goto err_free;
538 		}
539 
540 		if (json_output)
541 			jsonw_null(json_wtr);
542 	} else if (member_len == &info.jited_prog_len) {
543 		const char *name = NULL;
544 
545 		if (info.ifindex) {
546 			name = ifindex_to_bfd_name_ns(info.ifindex,
547 						      info.netns_dev,
548 						      info.netns_ino);
549 			if (!name)
550 				goto err_free;
551 		}
552 
553 		disasm_print_insn(buf, *member_len, opcodes, name);
554 	} else if (visual) {
555 		if (json_output)
556 			jsonw_null(json_wtr);
557 		else
558 			dump_xlated_cfg(buf, *member_len);
559 	} else {
560 		kernel_syms_load(&dd);
561 		if (json_output)
562 			dump_xlated_json(&dd, buf, *member_len, opcodes);
563 		else
564 			dump_xlated_plain(&dd, buf, *member_len, opcodes);
565 		kernel_syms_destroy(&dd);
566 	}
567 
568 	free(buf);
569 	return 0;
570 
571 err_free:
572 	free(buf);
573 	return -1;
574 }
575 
576 static int do_pin(int argc, char **argv)
577 {
578 	int err;
579 
580 	err = do_pin_any(argc, argv, bpf_prog_get_fd_by_id);
581 	if (!err && json_output)
582 		jsonw_null(json_wtr);
583 	return err;
584 }
585 
586 static int do_load(int argc, char **argv)
587 {
588 	struct bpf_object *obj;
589 	int prog_fd;
590 
591 	if (argc != 2)
592 		usage();
593 
594 	if (bpf_prog_load(argv[0], BPF_PROG_TYPE_UNSPEC, &obj, &prog_fd)) {
595 		p_err("failed to load program");
596 		return -1;
597 	}
598 
599 	if (do_pin_fd(prog_fd, argv[1])) {
600 		p_err("failed to pin program");
601 		return -1;
602 	}
603 
604 	if (json_output)
605 		jsonw_null(json_wtr);
606 
607 	return 0;
608 }
609 
610 static int do_help(int argc, char **argv)
611 {
612 	if (json_output) {
613 		jsonw_null(json_wtr);
614 		return 0;
615 	}
616 
617 	fprintf(stderr,
618 		"Usage: %s %s { show | list } [PROG]\n"
619 		"       %s %s dump xlated PROG [{ file FILE | opcodes | visual }]\n"
620 		"       %s %s dump jited  PROG [{ file FILE | opcodes }]\n"
621 		"       %s %s pin   PROG FILE\n"
622 		"       %s %s load  OBJ  FILE\n"
623 		"       %s %s help\n"
624 		"\n"
625 		"       " HELP_SPEC_PROGRAM "\n"
626 		"       " HELP_SPEC_OPTIONS "\n"
627 		"",
628 		bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2],
629 		bin_name, argv[-2], bin_name, argv[-2], bin_name, argv[-2]);
630 
631 	return 0;
632 }
633 
634 static const struct cmd cmds[] = {
635 	{ "show",	do_show },
636 	{ "list",	do_show },
637 	{ "help",	do_help },
638 	{ "dump",	do_dump },
639 	{ "pin",	do_pin },
640 	{ "load",	do_load },
641 	{ 0 }
642 };
643 
644 int do_prog(int argc, char **argv)
645 {
646 	return cmd_select(cmds, argc, argv, do_help);
647 }
648