xref: /openbmc/linux/tools/bpf/bpftool/main.c (revision 4eb5928d)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2017-2018 Netronome Systems, Inc. */
3 
4 #include <ctype.h>
5 #include <errno.h>
6 #include <getopt.h>
7 #include <linux/bpf.h>
8 #include <stdio.h>
9 #include <stdlib.h>
10 #include <string.h>
11 
12 #include <bpf/bpf.h>
13 #include <bpf/libbpf.h>
14 
15 #include "main.h"
16 
17 #define BATCH_LINE_LEN_MAX 65536
18 #define BATCH_ARG_NB_MAX 4096
19 
20 const char *bin_name;
21 static int last_argc;
22 static char **last_argv;
23 static int (*last_do_help)(int argc, char **argv);
24 json_writer_t *json_wtr;
25 bool pretty_output;
26 bool json_output;
27 bool show_pinned;
28 bool block_mount;
29 bool verifier_logs;
30 bool relaxed_maps;
31 struct pinned_obj_table prog_table;
32 struct pinned_obj_table map_table;
33 struct pinned_obj_table link_table;
34 struct obj_refs_table refs_table;
35 
36 static void __noreturn clean_and_exit(int i)
37 {
38 	if (json_output)
39 		jsonw_destroy(&json_wtr);
40 
41 	exit(i);
42 }
43 
44 void usage(void)
45 {
46 	last_do_help(last_argc - 1, last_argv + 1);
47 
48 	clean_and_exit(-1);
49 }
50 
51 static int do_help(int argc, char **argv)
52 {
53 	if (json_output) {
54 		jsonw_null(json_wtr);
55 		return 0;
56 	}
57 
58 	fprintf(stderr,
59 		"Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
60 		"       %s batch file FILE\n"
61 		"       %s version\n"
62 		"\n"
63 		"       OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n"
64 		"       " HELP_SPEC_OPTIONS "\n"
65 		"",
66 		bin_name, bin_name, bin_name);
67 
68 	return 0;
69 }
70 
71 static int do_version(int argc, char **argv)
72 {
73 	if (json_output) {
74 		jsonw_start_object(json_wtr);
75 		jsonw_name(json_wtr, "version");
76 		jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
77 		jsonw_end_object(json_wtr);
78 	} else {
79 		printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
80 	}
81 	return 0;
82 }
83 
84 int cmd_select(const struct cmd *cmds, int argc, char **argv,
85 	       int (*help)(int argc, char **argv))
86 {
87 	unsigned int i;
88 
89 	last_argc = argc;
90 	last_argv = argv;
91 	last_do_help = help;
92 
93 	if (argc < 1 && cmds[0].func)
94 		return cmds[0].func(argc, argv);
95 
96 	for (i = 0; cmds[i].cmd; i++) {
97 		if (is_prefix(*argv, cmds[i].cmd)) {
98 			if (!cmds[i].func) {
99 				p_err("command '%s' is not supported in bootstrap mode",
100 				      cmds[i].cmd);
101 				return -1;
102 			}
103 			return cmds[i].func(argc - 1, argv + 1);
104 		}
105 	}
106 
107 	help(argc - 1, argv + 1);
108 
109 	return -1;
110 }
111 
112 bool is_prefix(const char *pfx, const char *str)
113 {
114 	if (!pfx)
115 		return false;
116 	if (strlen(str) < strlen(pfx))
117 		return false;
118 
119 	return !memcmp(str, pfx, strlen(pfx));
120 }
121 
122 /* Last argument MUST be NULL pointer */
123 int detect_common_prefix(const char *arg, ...)
124 {
125 	unsigned int count = 0;
126 	const char *ref;
127 	char msg[256];
128 	va_list ap;
129 
130 	snprintf(msg, sizeof(msg), "ambiguous prefix: '%s' could be '", arg);
131 	va_start(ap, arg);
132 	while ((ref = va_arg(ap, const char *))) {
133 		if (!is_prefix(arg, ref))
134 			continue;
135 		count++;
136 		if (count > 1)
137 			strncat(msg, "' or '", sizeof(msg) - strlen(msg) - 1);
138 		strncat(msg, ref, sizeof(msg) - strlen(msg) - 1);
139 	}
140 	va_end(ap);
141 	strncat(msg, "'", sizeof(msg) - strlen(msg) - 1);
142 
143 	if (count >= 2) {
144 		p_err("%s", msg);
145 		return -1;
146 	}
147 
148 	return 0;
149 }
150 
151 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
152 {
153 	unsigned char *data = arg;
154 	unsigned int i;
155 
156 	for (i = 0; i < n; i++) {
157 		const char *pfx = "";
158 
159 		if (!i)
160 			/* nothing */;
161 		else if (!(i % 16))
162 			fprintf(f, "\n");
163 		else if (!(i % 8))
164 			fprintf(f, "  ");
165 		else
166 			pfx = sep;
167 
168 		fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
169 	}
170 }
171 
172 /* Split command line into argument vector. */
173 static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
174 {
175 	static const char ws[] = " \t\r\n";
176 	char *cp = line;
177 	int n_argc = 0;
178 
179 	while (*cp) {
180 		/* Skip leading whitespace. */
181 		cp += strspn(cp, ws);
182 
183 		if (*cp == '\0')
184 			break;
185 
186 		if (n_argc >= (maxargs - 1)) {
187 			p_err("too many arguments to command %d", cmd_nb);
188 			return -1;
189 		}
190 
191 		/* Word begins with quote. */
192 		if (*cp == '\'' || *cp == '"') {
193 			char quote = *cp++;
194 
195 			n_argv[n_argc++] = cp;
196 			/* Find ending quote. */
197 			cp = strchr(cp, quote);
198 			if (!cp) {
199 				p_err("unterminated quoted string in command %d",
200 				      cmd_nb);
201 				return -1;
202 			}
203 		} else {
204 			n_argv[n_argc++] = cp;
205 
206 			/* Find end of word. */
207 			cp += strcspn(cp, ws);
208 			if (*cp == '\0')
209 				break;
210 		}
211 
212 		/* Separate words. */
213 		*cp++ = 0;
214 	}
215 	n_argv[n_argc] = NULL;
216 
217 	return n_argc;
218 }
219 
220 static int do_batch(int argc, char **argv);
221 
222 static const struct cmd cmds[] = {
223 	{ "help",	do_help },
224 	{ "batch",	do_batch },
225 	{ "prog",	do_prog },
226 	{ "map",	do_map },
227 	{ "link",	do_link },
228 	{ "cgroup",	do_cgroup },
229 	{ "perf",	do_perf },
230 	{ "net",	do_net },
231 	{ "feature",	do_feature },
232 	{ "btf",	do_btf },
233 	{ "gen",	do_gen },
234 	{ "struct_ops",	do_struct_ops },
235 	{ "iter",	do_iter },
236 	{ "version",	do_version },
237 	{ 0 }
238 };
239 
240 static int do_batch(int argc, char **argv)
241 {
242 	char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
243 	char *n_argv[BATCH_ARG_NB_MAX];
244 	unsigned int lines = 0;
245 	int n_argc;
246 	FILE *fp;
247 	char *cp;
248 	int err;
249 	int i;
250 
251 	if (argc < 2) {
252 		p_err("too few parameters for batch");
253 		return -1;
254 	} else if (!is_prefix(*argv, "file")) {
255 		p_err("expected 'file', got: %s", *argv);
256 		return -1;
257 	} else if (argc > 2) {
258 		p_err("too many parameters for batch");
259 		return -1;
260 	}
261 	NEXT_ARG();
262 
263 	if (!strcmp(*argv, "-"))
264 		fp = stdin;
265 	else
266 		fp = fopen(*argv, "r");
267 	if (!fp) {
268 		p_err("Can't open file (%s): %s", *argv, strerror(errno));
269 		return -1;
270 	}
271 
272 	if (json_output)
273 		jsonw_start_array(json_wtr);
274 	while (fgets(buf, sizeof(buf), fp)) {
275 		cp = strchr(buf, '#');
276 		if (cp)
277 			*cp = '\0';
278 
279 		if (strlen(buf) == sizeof(buf) - 1) {
280 			errno = E2BIG;
281 			break;
282 		}
283 
284 		/* Append continuation lines if any (coming after a line ending
285 		 * with '\' in the batch file).
286 		 */
287 		while ((cp = strstr(buf, "\\\n")) != NULL) {
288 			if (!fgets(contline, sizeof(contline), fp) ||
289 			    strlen(contline) == 0) {
290 				p_err("missing continuation line on command %d",
291 				      lines);
292 				err = -1;
293 				goto err_close;
294 			}
295 
296 			cp = strchr(contline, '#');
297 			if (cp)
298 				*cp = '\0';
299 
300 			if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
301 				p_err("command %d is too long", lines);
302 				err = -1;
303 				goto err_close;
304 			}
305 			buf[strlen(buf) - 2] = '\0';
306 			strcat(buf, contline);
307 		}
308 
309 		n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
310 		if (!n_argc)
311 			continue;
312 		if (n_argc < 0)
313 			goto err_close;
314 
315 		if (json_output) {
316 			jsonw_start_object(json_wtr);
317 			jsonw_name(json_wtr, "command");
318 			jsonw_start_array(json_wtr);
319 			for (i = 0; i < n_argc; i++)
320 				jsonw_string(json_wtr, n_argv[i]);
321 			jsonw_end_array(json_wtr);
322 			jsonw_name(json_wtr, "output");
323 		}
324 
325 		err = cmd_select(cmds, n_argc, n_argv, do_help);
326 
327 		if (json_output)
328 			jsonw_end_object(json_wtr);
329 
330 		if (err)
331 			goto err_close;
332 
333 		lines++;
334 	}
335 
336 	if (errno && errno != ENOENT) {
337 		p_err("reading batch file failed: %s", strerror(errno));
338 		err = -1;
339 	} else {
340 		if (!json_output)
341 			printf("processed %d commands\n", lines);
342 		err = 0;
343 	}
344 err_close:
345 	if (fp != stdin)
346 		fclose(fp);
347 
348 	if (json_output)
349 		jsonw_end_array(json_wtr);
350 
351 	return err;
352 }
353 
354 int main(int argc, char **argv)
355 {
356 	static const struct option options[] = {
357 		{ "json",	no_argument,	NULL,	'j' },
358 		{ "help",	no_argument,	NULL,	'h' },
359 		{ "pretty",	no_argument,	NULL,	'p' },
360 		{ "version",	no_argument,	NULL,	'V' },
361 		{ "bpffs",	no_argument,	NULL,	'f' },
362 		{ "mapcompat",	no_argument,	NULL,	'm' },
363 		{ "nomount",	no_argument,	NULL,	'n' },
364 		{ "debug",	no_argument,	NULL,	'd' },
365 		{ 0 }
366 	};
367 	int opt, ret;
368 
369 	last_do_help = do_help;
370 	pretty_output = false;
371 	json_output = false;
372 	show_pinned = false;
373 	block_mount = false;
374 	bin_name = argv[0];
375 
376 	hash_init(prog_table.table);
377 	hash_init(map_table.table);
378 	hash_init(link_table.table);
379 
380 	opterr = 0;
381 	while ((opt = getopt_long(argc, argv, "Vhpjfmnd",
382 				  options, NULL)) >= 0) {
383 		switch (opt) {
384 		case 'V':
385 			return do_version(argc, argv);
386 		case 'h':
387 			return do_help(argc, argv);
388 		case 'p':
389 			pretty_output = true;
390 			/* fall through */
391 		case 'j':
392 			if (!json_output) {
393 				json_wtr = jsonw_new(stdout);
394 				if (!json_wtr) {
395 					p_err("failed to create JSON writer");
396 					return -1;
397 				}
398 				json_output = true;
399 			}
400 			jsonw_pretty(json_wtr, pretty_output);
401 			break;
402 		case 'f':
403 			show_pinned = true;
404 			break;
405 		case 'm':
406 			relaxed_maps = true;
407 			break;
408 		case 'n':
409 			block_mount = true;
410 			break;
411 		case 'd':
412 			libbpf_set_print(print_all_levels);
413 			verifier_logs = true;
414 			break;
415 		default:
416 			p_err("unrecognized option '%s'", argv[optind - 1]);
417 			if (json_output)
418 				clean_and_exit(-1);
419 			else
420 				usage();
421 		}
422 	}
423 
424 	argc -= optind;
425 	argv += optind;
426 	if (argc < 0)
427 		usage();
428 
429 	ret = cmd_select(cmds, argc, argv, do_help);
430 
431 	if (json_output)
432 		jsonw_destroy(&json_wtr);
433 
434 	if (show_pinned) {
435 		delete_pinned_obj_table(&prog_table);
436 		delete_pinned_obj_table(&map_table);
437 		delete_pinned_obj_table(&link_table);
438 	}
439 
440 	return ret;
441 }
442