xref: /openbmc/linux/tools/bpf/bpftool/main.c (revision 2eb3ed33e55d003d721d4d1a5e72fe323c12b4c0)
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 <linux/version.h>
42 #include <stdio.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include <bpf.h>
47 
48 #include "main.h"
49 
50 const char *bin_name;
51 static int last_argc;
52 static char **last_argv;
53 static int (*last_do_help)(int argc, char **argv);
54 json_writer_t *json_wtr;
55 bool pretty_output;
56 bool json_output;
57 
58 void usage(void)
59 {
60 	last_do_help(last_argc - 1, last_argv + 1);
61 
62 	exit(-1);
63 }
64 
65 static int do_help(int argc, char **argv)
66 {
67 	if (json_output) {
68 		jsonw_null(json_wtr);
69 		return 0;
70 	}
71 
72 	fprintf(stderr,
73 		"Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
74 		"       %s batch file FILE\n"
75 		"       %s version\n"
76 		"\n"
77 		"       OBJECT := { prog | map }\n"
78 		"       " HELP_SPEC_OPTIONS "\n"
79 		"",
80 		bin_name, bin_name, bin_name);
81 
82 	return 0;
83 }
84 
85 static int do_version(int argc, char **argv)
86 {
87 	unsigned int version[3];
88 
89 	version[0] = LINUX_VERSION_CODE >> 16;
90 	version[1] = LINUX_VERSION_CODE >> 8 & 0xf;
91 	version[2] = LINUX_VERSION_CODE & 0xf;
92 
93 	if (json_output) {
94 		jsonw_start_object(json_wtr);
95 		jsonw_name(json_wtr, "version");
96 		jsonw_printf(json_wtr, "\"%u.%u.%u\"",
97 			     version[0], version[1], version[2]);
98 		jsonw_end_object(json_wtr);
99 	} else {
100 		printf("%s v%u.%u.%u\n", bin_name,
101 		       version[0], version[1], version[2]);
102 	}
103 	return 0;
104 }
105 
106 int cmd_select(const struct cmd *cmds, int argc, char **argv,
107 	       int (*help)(int argc, char **argv))
108 {
109 	unsigned int i;
110 
111 	last_argc = argc;
112 	last_argv = argv;
113 	last_do_help = help;
114 
115 	if (argc < 1 && cmds[0].func)
116 		return cmds[0].func(argc, argv);
117 
118 	for (i = 0; cmds[i].func; i++)
119 		if (is_prefix(*argv, cmds[i].cmd))
120 			return cmds[i].func(argc - 1, argv + 1);
121 
122 	help(argc - 1, argv + 1);
123 
124 	return -1;
125 }
126 
127 bool is_prefix(const char *pfx, const char *str)
128 {
129 	if (!pfx)
130 		return false;
131 	if (strlen(str) < strlen(pfx))
132 		return false;
133 
134 	return !memcmp(str, pfx, strlen(pfx));
135 }
136 
137 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
138 {
139 	unsigned char *data = arg;
140 	unsigned int i;
141 
142 	for (i = 0; i < n; i++) {
143 		const char *pfx = "";
144 
145 		if (!i)
146 			/* nothing */;
147 		else if (!(i % 16))
148 			fprintf(f, "\n");
149 		else if (!(i % 8))
150 			fprintf(f, "  ");
151 		else
152 			pfx = sep;
153 
154 		fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
155 	}
156 }
157 
158 static int do_batch(int argc, char **argv);
159 
160 static const struct cmd cmds[] = {
161 	{ "help",	do_help },
162 	{ "batch",	do_batch },
163 	{ "prog",	do_prog },
164 	{ "map",	do_map },
165 	{ "version",	do_version },
166 	{ 0 }
167 };
168 
169 static int do_batch(int argc, char **argv)
170 {
171 	unsigned int lines = 0;
172 	char *n_argv[4096];
173 	char buf[65536];
174 	int n_argc;
175 	FILE *fp;
176 	int err;
177 	int i;
178 
179 	if (argc < 2) {
180 		p_err("too few parameters for batch");
181 		return -1;
182 	} else if (!is_prefix(*argv, "file")) {
183 		p_err("expected 'file', got: %s", *argv);
184 		return -1;
185 	} else if (argc > 2) {
186 		p_err("too many parameters for batch");
187 		return -1;
188 	}
189 	NEXT_ARG();
190 
191 	fp = fopen(*argv, "r");
192 	if (!fp) {
193 		p_err("Can't open file (%s): %s", *argv, strerror(errno));
194 		return -1;
195 	}
196 
197 	if (json_output)
198 		jsonw_start_array(json_wtr);
199 	while (fgets(buf, sizeof(buf), fp)) {
200 		if (strlen(buf) == sizeof(buf) - 1) {
201 			errno = E2BIG;
202 			break;
203 		}
204 
205 		n_argc = 0;
206 		n_argv[n_argc] = strtok(buf, " \t\n");
207 
208 		while (n_argv[n_argc]) {
209 			n_argc++;
210 			if (n_argc == ARRAY_SIZE(n_argv)) {
211 				p_err("line %d has too many arguments, skip",
212 				      lines);
213 				n_argc = 0;
214 				break;
215 			}
216 			n_argv[n_argc] = strtok(NULL, " \t\n");
217 		}
218 
219 		if (!n_argc)
220 			continue;
221 
222 		if (json_output) {
223 			jsonw_start_object(json_wtr);
224 			jsonw_name(json_wtr, "command");
225 			jsonw_start_array(json_wtr);
226 			for (i = 0; i < n_argc; i++)
227 				jsonw_string(json_wtr, n_argv[i]);
228 			jsonw_end_array(json_wtr);
229 			jsonw_name(json_wtr, "output");
230 		}
231 
232 		err = cmd_select(cmds, n_argc, n_argv, do_help);
233 
234 		if (json_output)
235 			jsonw_end_object(json_wtr);
236 
237 		if (err)
238 			goto err_close;
239 
240 		lines++;
241 	}
242 
243 	if (errno && errno != ENOENT) {
244 		perror("reading batch file failed");
245 		err = -1;
246 	} else {
247 		p_info("processed %d lines", lines);
248 		err = 0;
249 	}
250 err_close:
251 	fclose(fp);
252 
253 	if (json_output)
254 		jsonw_end_array(json_wtr);
255 
256 	return err;
257 }
258 
259 int main(int argc, char **argv)
260 {
261 	static const struct option options[] = {
262 		{ "json",	no_argument,	NULL,	'j' },
263 		{ "help",	no_argument,	NULL,	'h' },
264 		{ "pretty",	no_argument,	NULL,	'p' },
265 		{ "version",	no_argument,	NULL,	'V' },
266 		{ 0 }
267 	};
268 	int opt, ret;
269 
270 	last_do_help = do_help;
271 	pretty_output = false;
272 	json_output = false;
273 	bin_name = argv[0];
274 
275 	while ((opt = getopt_long(argc, argv, "Vhpj",
276 				  options, NULL)) >= 0) {
277 		switch (opt) {
278 		case 'V':
279 			return do_version(argc, argv);
280 		case 'h':
281 			return do_help(argc, argv);
282 		case 'p':
283 			pretty_output = true;
284 			/* fall through */
285 		case 'j':
286 			json_output = true;
287 			break;
288 		default:
289 			usage();
290 		}
291 	}
292 
293 	argc -= optind;
294 	argv += optind;
295 	if (argc < 0)
296 		usage();
297 
298 	if (json_output) {
299 		json_wtr = jsonw_new(stdout);
300 		if (!json_wtr) {
301 			p_err("failed to create JSON writer");
302 			return -1;
303 		}
304 		jsonw_pretty(json_wtr, pretty_output);
305 	}
306 
307 	bfd_init();
308 
309 	ret = cmd_select(cmds, argc, argv, do_help);
310 
311 	if (json_output)
312 		jsonw_destroy(&json_wtr);
313 
314 	return ret;
315 }
316