xref: /openbmc/linux/tools/bpf/bpftool/main.c (revision 2359ccdd)
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 <bfd.h>
37 #include <ctype.h>
38 #include <errno.h>
39 #include <getopt.h>
40 #include <linux/bpf.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 #include <string.h>
44 
45 #include <bpf.h>
46 
47 #include "main.h"
48 
49 #define BATCH_LINE_LEN_MAX 65536
50 #define BATCH_ARG_NB_MAX 4096
51 
52 const char *bin_name;
53 static int last_argc;
54 static char **last_argv;
55 static int (*last_do_help)(int argc, char **argv);
56 json_writer_t *json_wtr;
57 bool pretty_output;
58 bool json_output;
59 bool show_pinned;
60 struct pinned_obj_table prog_table;
61 struct pinned_obj_table map_table;
62 
63 static void __noreturn clean_and_exit(int i)
64 {
65 	if (json_output)
66 		jsonw_destroy(&json_wtr);
67 
68 	exit(i);
69 }
70 
71 void usage(void)
72 {
73 	last_do_help(last_argc - 1, last_argv + 1);
74 
75 	clean_and_exit(-1);
76 }
77 
78 static int do_help(int argc, char **argv)
79 {
80 	if (json_output) {
81 		jsonw_null(json_wtr);
82 		return 0;
83 	}
84 
85 	fprintf(stderr,
86 		"Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
87 		"       %s batch file FILE\n"
88 		"       %s version\n"
89 		"\n"
90 		"       OBJECT := { prog | map | cgroup }\n"
91 		"       " HELP_SPEC_OPTIONS "\n"
92 		"",
93 		bin_name, bin_name, bin_name);
94 
95 	return 0;
96 }
97 
98 static int do_version(int argc, char **argv)
99 {
100 	if (json_output) {
101 		jsonw_start_object(json_wtr);
102 		jsonw_name(json_wtr, "version");
103 		jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
104 		jsonw_end_object(json_wtr);
105 	} else {
106 		printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
107 	}
108 	return 0;
109 }
110 
111 int cmd_select(const struct cmd *cmds, int argc, char **argv,
112 	       int (*help)(int argc, char **argv))
113 {
114 	unsigned int i;
115 
116 	last_argc = argc;
117 	last_argv = argv;
118 	last_do_help = help;
119 
120 	if (argc < 1 && cmds[0].func)
121 		return cmds[0].func(argc, argv);
122 
123 	for (i = 0; cmds[i].func; i++)
124 		if (is_prefix(*argv, cmds[i].cmd))
125 			return cmds[i].func(argc - 1, argv + 1);
126 
127 	help(argc - 1, argv + 1);
128 
129 	return -1;
130 }
131 
132 bool is_prefix(const char *pfx, const char *str)
133 {
134 	if (!pfx)
135 		return false;
136 	if (strlen(str) < strlen(pfx))
137 		return false;
138 
139 	return !memcmp(str, pfx, strlen(pfx));
140 }
141 
142 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
143 {
144 	unsigned char *data = arg;
145 	unsigned int i;
146 
147 	for (i = 0; i < n; i++) {
148 		const char *pfx = "";
149 
150 		if (!i)
151 			/* nothing */;
152 		else if (!(i % 16))
153 			fprintf(f, "\n");
154 		else if (!(i % 8))
155 			fprintf(f, "  ");
156 		else
157 			pfx = sep;
158 
159 		fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
160 	}
161 }
162 
163 /* Split command line into argument vector. */
164 static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
165 {
166 	static const char ws[] = " \t\r\n";
167 	char *cp = line;
168 	int n_argc = 0;
169 
170 	while (*cp) {
171 		/* Skip leading whitespace. */
172 		cp += strspn(cp, ws);
173 
174 		if (*cp == '\0')
175 			break;
176 
177 		if (n_argc >= (maxargs - 1)) {
178 			p_err("too many arguments to command %d", cmd_nb);
179 			return -1;
180 		}
181 
182 		/* Word begins with quote. */
183 		if (*cp == '\'' || *cp == '"') {
184 			char quote = *cp++;
185 
186 			n_argv[n_argc++] = cp;
187 			/* Find ending quote. */
188 			cp = strchr(cp, quote);
189 			if (!cp) {
190 				p_err("unterminated quoted string in command %d",
191 				      cmd_nb);
192 				return -1;
193 			}
194 		} else {
195 			n_argv[n_argc++] = cp;
196 
197 			/* Find end of word. */
198 			cp += strcspn(cp, ws);
199 			if (*cp == '\0')
200 				break;
201 		}
202 
203 		/* Separate words. */
204 		*cp++ = 0;
205 	}
206 	n_argv[n_argc] = NULL;
207 
208 	return n_argc;
209 }
210 
211 static int do_batch(int argc, char **argv);
212 
213 static const struct cmd cmds[] = {
214 	{ "help",	do_help },
215 	{ "batch",	do_batch },
216 	{ "prog",	do_prog },
217 	{ "map",	do_map },
218 	{ "cgroup",	do_cgroup },
219 	{ "version",	do_version },
220 	{ 0 }
221 };
222 
223 static int do_batch(int argc, char **argv)
224 {
225 	char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
226 	char *n_argv[BATCH_ARG_NB_MAX];
227 	unsigned int lines = 0;
228 	int n_argc;
229 	FILE *fp;
230 	char *cp;
231 	int err;
232 	int i;
233 
234 	if (argc < 2) {
235 		p_err("too few parameters for batch");
236 		return -1;
237 	} else if (!is_prefix(*argv, "file")) {
238 		p_err("expected 'file', got: %s", *argv);
239 		return -1;
240 	} else if (argc > 2) {
241 		p_err("too many parameters for batch");
242 		return -1;
243 	}
244 	NEXT_ARG();
245 
246 	if (!strcmp(*argv, "-"))
247 		fp = stdin;
248 	else
249 		fp = fopen(*argv, "r");
250 	if (!fp) {
251 		p_err("Can't open file (%s): %s", *argv, strerror(errno));
252 		return -1;
253 	}
254 
255 	if (json_output)
256 		jsonw_start_array(json_wtr);
257 	while (fgets(buf, sizeof(buf), fp)) {
258 		cp = strchr(buf, '#');
259 		if (cp)
260 			*cp = '\0';
261 
262 		if (strlen(buf) == sizeof(buf) - 1) {
263 			errno = E2BIG;
264 			break;
265 		}
266 
267 		/* Append continuation lines if any (coming after a line ending
268 		 * with '\' in the batch file).
269 		 */
270 		while ((cp = strstr(buf, "\\\n")) != NULL) {
271 			if (!fgets(contline, sizeof(contline), fp) ||
272 			    strlen(contline) == 0) {
273 				p_err("missing continuation line on command %d",
274 				      lines);
275 				err = -1;
276 				goto err_close;
277 			}
278 
279 			cp = strchr(contline, '#');
280 			if (cp)
281 				*cp = '\0';
282 
283 			if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
284 				p_err("command %d is too long", lines);
285 				err = -1;
286 				goto err_close;
287 			}
288 			buf[strlen(buf) - 2] = '\0';
289 			strcat(buf, contline);
290 		}
291 
292 		n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
293 		if (!n_argc)
294 			continue;
295 		if (n_argc < 0)
296 			goto err_close;
297 
298 		if (json_output) {
299 			jsonw_start_object(json_wtr);
300 			jsonw_name(json_wtr, "command");
301 			jsonw_start_array(json_wtr);
302 			for (i = 0; i < n_argc; i++)
303 				jsonw_string(json_wtr, n_argv[i]);
304 			jsonw_end_array(json_wtr);
305 			jsonw_name(json_wtr, "output");
306 		}
307 
308 		err = cmd_select(cmds, n_argc, n_argv, do_help);
309 
310 		if (json_output)
311 			jsonw_end_object(json_wtr);
312 
313 		if (err)
314 			goto err_close;
315 
316 		lines++;
317 	}
318 
319 	if (errno && errno != ENOENT) {
320 		p_err("reading batch file failed: %s", strerror(errno));
321 		err = -1;
322 	} else {
323 		p_info("processed %d commands", lines);
324 		err = 0;
325 	}
326 err_close:
327 	if (fp != stdin)
328 		fclose(fp);
329 
330 	if (json_output)
331 		jsonw_end_array(json_wtr);
332 
333 	return err;
334 }
335 
336 int main(int argc, char **argv)
337 {
338 	static const struct option options[] = {
339 		{ "json",	no_argument,	NULL,	'j' },
340 		{ "help",	no_argument,	NULL,	'h' },
341 		{ "pretty",	no_argument,	NULL,	'p' },
342 		{ "version",	no_argument,	NULL,	'V' },
343 		{ "bpffs",	no_argument,	NULL,	'f' },
344 		{ 0 }
345 	};
346 	int opt, ret;
347 
348 	last_do_help = do_help;
349 	pretty_output = false;
350 	json_output = false;
351 	show_pinned = false;
352 	bin_name = argv[0];
353 
354 	hash_init(prog_table.table);
355 	hash_init(map_table.table);
356 
357 	opterr = 0;
358 	while ((opt = getopt_long(argc, argv, "Vhpjf",
359 				  options, NULL)) >= 0) {
360 		switch (opt) {
361 		case 'V':
362 			return do_version(argc, argv);
363 		case 'h':
364 			return do_help(argc, argv);
365 		case 'p':
366 			pretty_output = true;
367 			/* fall through */
368 		case 'j':
369 			if (!json_output) {
370 				json_wtr = jsonw_new(stdout);
371 				if (!json_wtr) {
372 					p_err("failed to create JSON writer");
373 					return -1;
374 				}
375 				json_output = true;
376 			}
377 			jsonw_pretty(json_wtr, pretty_output);
378 			break;
379 		case 'f':
380 			show_pinned = true;
381 			break;
382 		default:
383 			p_err("unrecognized option '%s'", argv[optind - 1]);
384 			if (json_output)
385 				clean_and_exit(-1);
386 			else
387 				usage();
388 		}
389 	}
390 
391 	argc -= optind;
392 	argv += optind;
393 	if (argc < 0)
394 		usage();
395 
396 	bfd_init();
397 
398 	ret = cmd_select(cmds, argc, argv, do_help);
399 
400 	if (json_output)
401 		jsonw_destroy(&json_wtr);
402 
403 	if (show_pinned) {
404 		delete_pinned_obj_table(&prog_table);
405 		delete_pinned_obj_table(&map_table);
406 	}
407 
408 	return ret;
409 }
410