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.h>
13 #include <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 int bpf_flags;
31 struct pinned_obj_table prog_table;
32 struct pinned_obj_table map_table;
33
clean_and_exit(int i)34 static void __noreturn clean_and_exit(int i)
35 {
36 if (json_output)
37 jsonw_destroy(&json_wtr);
38
39 exit(i);
40 }
41
usage(void)42 void usage(void)
43 {
44 last_do_help(last_argc - 1, last_argv + 1);
45
46 clean_and_exit(-1);
47 }
48
do_help(int argc,char ** argv)49 static int do_help(int argc, char **argv)
50 {
51 if (json_output) {
52 jsonw_null(json_wtr);
53 return 0;
54 }
55
56 fprintf(stderr,
57 "Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
58 " %s batch file FILE\n"
59 " %s version\n"
60 "\n"
61 " OBJECT := { prog | map | cgroup | perf | net | feature | btf }\n"
62 " " HELP_SPEC_OPTIONS "\n"
63 "",
64 bin_name, bin_name, bin_name);
65
66 return 0;
67 }
68
do_version(int argc,char ** argv)69 static int do_version(int argc, char **argv)
70 {
71 if (json_output) {
72 jsonw_start_object(json_wtr);
73 jsonw_name(json_wtr, "version");
74 jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
75 jsonw_end_object(json_wtr);
76 } else {
77 printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
78 }
79 return 0;
80 }
81
82 static int __printf(2, 0)
print_all_levels(__maybe_unused enum libbpf_print_level level,const char * format,va_list args)83 print_all_levels(__maybe_unused enum libbpf_print_level level,
84 const char *format, va_list args)
85 {
86 return vfprintf(stderr, format, args);
87 }
88
cmd_select(const struct cmd * cmds,int argc,char ** argv,int (* help)(int argc,char ** argv))89 int cmd_select(const struct cmd *cmds, int argc, char **argv,
90 int (*help)(int argc, char **argv))
91 {
92 unsigned int i;
93
94 last_argc = argc;
95 last_argv = argv;
96 last_do_help = help;
97
98 if (argc < 1 && cmds[0].func)
99 return cmds[0].func(argc, argv);
100
101 for (i = 0; cmds[i].func; i++)
102 if (is_prefix(*argv, cmds[i].cmd))
103 return cmds[i].func(argc - 1, argv + 1);
104
105 help(argc - 1, argv + 1);
106
107 return -1;
108 }
109
is_prefix(const char * pfx,const char * str)110 bool is_prefix(const char *pfx, const char *str)
111 {
112 if (!pfx)
113 return false;
114 if (strlen(str) < strlen(pfx))
115 return false;
116
117 return !memcmp(str, pfx, strlen(pfx));
118 }
119
120 /* Last argument MUST be NULL pointer */
detect_common_prefix(const char * arg,...)121 int detect_common_prefix(const char *arg, ...)
122 {
123 unsigned int count = 0;
124 const char *ref;
125 char msg[256];
126 va_list ap;
127
128 snprintf(msg, sizeof(msg), "ambiguous prefix: '%s' could be '", arg);
129 va_start(ap, arg);
130 while ((ref = va_arg(ap, const char *))) {
131 if (!is_prefix(arg, ref))
132 continue;
133 count++;
134 if (count > 1)
135 strncat(msg, "' or '", sizeof(msg) - strlen(msg) - 1);
136 strncat(msg, ref, sizeof(msg) - strlen(msg) - 1);
137 }
138 va_end(ap);
139 strncat(msg, "'", sizeof(msg) - strlen(msg) - 1);
140
141 if (count >= 2) {
142 p_err("%s", msg);
143 return -1;
144 }
145
146 return 0;
147 }
148
fprint_hex(FILE * f,void * arg,unsigned int n,const char * sep)149 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
150 {
151 unsigned char *data = arg;
152 unsigned int i;
153
154 for (i = 0; i < n; i++) {
155 const char *pfx = "";
156
157 if (!i)
158 /* nothing */;
159 else if (!(i % 16))
160 fprintf(f, "\n");
161 else if (!(i % 8))
162 fprintf(f, " ");
163 else
164 pfx = sep;
165
166 fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
167 }
168 }
169
170 /* Split command line into argument vector. */
make_args(char * line,char * n_argv[],int maxargs,int cmd_nb)171 static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
172 {
173 static const char ws[] = " \t\r\n";
174 char *cp = line;
175 int n_argc = 0;
176
177 while (*cp) {
178 /* Skip leading whitespace. */
179 cp += strspn(cp, ws);
180
181 if (*cp == '\0')
182 break;
183
184 if (n_argc >= (maxargs - 1)) {
185 p_err("too many arguments to command %d", cmd_nb);
186 return -1;
187 }
188
189 /* Word begins with quote. */
190 if (*cp == '\'' || *cp == '"') {
191 char quote = *cp++;
192
193 n_argv[n_argc++] = cp;
194 /* Find ending quote. */
195 cp = strchr(cp, quote);
196 if (!cp) {
197 p_err("unterminated quoted string in command %d",
198 cmd_nb);
199 return -1;
200 }
201 } else {
202 n_argv[n_argc++] = cp;
203
204 /* Find end of word. */
205 cp += strcspn(cp, ws);
206 if (*cp == '\0')
207 break;
208 }
209
210 /* Separate words. */
211 *cp++ = 0;
212 }
213 n_argv[n_argc] = NULL;
214
215 return n_argc;
216 }
217
218 static int do_batch(int argc, char **argv);
219
220 static const struct cmd cmds[] = {
221 { "help", do_help },
222 { "batch", do_batch },
223 { "prog", do_prog },
224 { "map", do_map },
225 { "cgroup", do_cgroup },
226 { "perf", do_perf },
227 { "net", do_net },
228 { "feature", do_feature },
229 { "btf", do_btf },
230 { "version", do_version },
231 { 0 }
232 };
233
do_batch(int argc,char ** argv)234 static int do_batch(int argc, char **argv)
235 {
236 char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
237 char *n_argv[BATCH_ARG_NB_MAX];
238 unsigned int lines = 0;
239 int n_argc;
240 FILE *fp;
241 char *cp;
242 int err;
243 int i;
244
245 if (argc < 2) {
246 p_err("too few parameters for batch");
247 return -1;
248 } else if (!is_prefix(*argv, "file")) {
249 p_err("expected 'file', got: %s", *argv);
250 return -1;
251 } else if (argc > 2) {
252 p_err("too many parameters for batch");
253 return -1;
254 }
255 NEXT_ARG();
256
257 if (!strcmp(*argv, "-"))
258 fp = stdin;
259 else
260 fp = fopen(*argv, "r");
261 if (!fp) {
262 p_err("Can't open file (%s): %s", *argv, strerror(errno));
263 return -1;
264 }
265
266 if (json_output)
267 jsonw_start_array(json_wtr);
268 while (fgets(buf, sizeof(buf), fp)) {
269 cp = strchr(buf, '#');
270 if (cp)
271 *cp = '\0';
272
273 if (strlen(buf) == sizeof(buf) - 1) {
274 errno = E2BIG;
275 break;
276 }
277
278 /* Append continuation lines if any (coming after a line ending
279 * with '\' in the batch file).
280 */
281 while ((cp = strstr(buf, "\\\n")) != NULL) {
282 if (!fgets(contline, sizeof(contline), fp) ||
283 strlen(contline) == 0) {
284 p_err("missing continuation line on command %d",
285 lines);
286 err = -1;
287 goto err_close;
288 }
289
290 cp = strchr(contline, '#');
291 if (cp)
292 *cp = '\0';
293
294 if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
295 p_err("command %d is too long", lines);
296 err = -1;
297 goto err_close;
298 }
299 buf[strlen(buf) - 2] = '\0';
300 strcat(buf, contline);
301 }
302
303 n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
304 if (!n_argc)
305 continue;
306 if (n_argc < 0) {
307 err = n_argc;
308 goto err_close;
309 }
310
311 if (json_output) {
312 jsonw_start_object(json_wtr);
313 jsonw_name(json_wtr, "command");
314 jsonw_start_array(json_wtr);
315 for (i = 0; i < n_argc; i++)
316 jsonw_string(json_wtr, n_argv[i]);
317 jsonw_end_array(json_wtr);
318 jsonw_name(json_wtr, "output");
319 }
320
321 err = cmd_select(cmds, n_argc, n_argv, do_help);
322
323 if (json_output)
324 jsonw_end_object(json_wtr);
325
326 if (err)
327 goto err_close;
328
329 lines++;
330 }
331
332 if (errno && errno != ENOENT) {
333 p_err("reading batch file failed: %s", strerror(errno));
334 err = -1;
335 } else {
336 if (!json_output)
337 printf("processed %d commands\n", lines);
338 err = 0;
339 }
340 err_close:
341 if (fp != stdin)
342 fclose(fp);
343
344 if (json_output)
345 jsonw_end_array(json_wtr);
346
347 return err;
348 }
349
main(int argc,char ** argv)350 int main(int argc, char **argv)
351 {
352 static const struct option options[] = {
353 { "json", no_argument, NULL, 'j' },
354 { "help", no_argument, NULL, 'h' },
355 { "pretty", no_argument, NULL, 'p' },
356 { "version", no_argument, NULL, 'V' },
357 { "bpffs", no_argument, NULL, 'f' },
358 { "mapcompat", no_argument, NULL, 'm' },
359 { "nomount", no_argument, NULL, 'n' },
360 { "debug", no_argument, NULL, 'd' },
361 { 0 }
362 };
363 int opt, ret;
364
365 setlinebuf(stdout);
366
367 #ifdef USE_LIBCAP
368 /* Libcap < 2.63 hooks before main() to compute the number of
369 * capabilities of the running kernel, and doing so it calls prctl()
370 * which may fail and set errno to non-zero.
371 * Let's reset errno to make sure this does not interfere with the
372 * batch mode.
373 */
374 errno = 0;
375 #endif
376
377 last_do_help = do_help;
378 pretty_output = false;
379 json_output = false;
380 show_pinned = false;
381 block_mount = false;
382 bin_name = argv[0];
383
384 hash_init(prog_table.table);
385 hash_init(map_table.table);
386
387 opterr = 0;
388 while ((opt = getopt_long(argc, argv, "Vhpjfmnd",
389 options, NULL)) >= 0) {
390 switch (opt) {
391 case 'V':
392 return do_version(argc, argv);
393 case 'h':
394 return do_help(argc, argv);
395 case 'p':
396 pretty_output = true;
397 /* fall through */
398 case 'j':
399 if (!json_output) {
400 json_wtr = jsonw_new(stdout);
401 if (!json_wtr) {
402 p_err("failed to create JSON writer");
403 return -1;
404 }
405 json_output = true;
406 }
407 jsonw_pretty(json_wtr, pretty_output);
408 break;
409 case 'f':
410 show_pinned = true;
411 break;
412 case 'm':
413 bpf_flags = MAPS_RELAX_COMPAT;
414 break;
415 case 'n':
416 block_mount = true;
417 break;
418 case 'd':
419 libbpf_set_print(print_all_levels);
420 verifier_logs = true;
421 break;
422 default:
423 p_err("unrecognized option '%s'", argv[optind - 1]);
424 if (json_output)
425 clean_and_exit(-1);
426 else
427 usage();
428 }
429 }
430
431 argc -= optind;
432 argv += optind;
433 if (argc < 0)
434 usage();
435
436 ret = cmd_select(cmds, argc, argv, do_help);
437
438 if (json_output)
439 jsonw_destroy(&json_wtr);
440
441 if (show_pinned) {
442 delete_pinned_obj_table(&prog_table);
443 delete_pinned_obj_table(&map_table);
444 }
445
446 return ret;
447 }
448