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/btf.h>
14 #include <bpf/hashmap.h>
15 #include <bpf/libbpf.h>
16
17 #include "main.h"
18
19 #define BATCH_LINE_LEN_MAX 65536
20 #define BATCH_ARG_NB_MAX 4096
21
22 const char *bin_name;
23 static int last_argc;
24 static char **last_argv;
25 static int (*last_do_help)(int argc, char **argv);
26 json_writer_t *json_wtr;
27 bool pretty_output;
28 bool json_output;
29 bool show_pinned;
30 bool block_mount;
31 bool verifier_logs;
32 bool relaxed_maps;
33 bool use_loader;
34 bool legacy_libbpf;
35 struct btf *base_btf;
36 struct hashmap *refs_table;
37
clean_and_exit(int i)38 static void __noreturn clean_and_exit(int i)
39 {
40 if (json_output)
41 jsonw_destroy(&json_wtr);
42
43 exit(i);
44 }
45
usage(void)46 void usage(void)
47 {
48 last_do_help(last_argc - 1, last_argv + 1);
49
50 clean_and_exit(-1);
51 }
52
do_help(int argc,char ** argv)53 static int do_help(int argc, char **argv)
54 {
55 if (json_output) {
56 jsonw_null(json_wtr);
57 return 0;
58 }
59
60 fprintf(stderr,
61 "Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
62 " %s batch file FILE\n"
63 " %s version\n"
64 "\n"
65 " OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n"
66 " " HELP_SPEC_OPTIONS " |\n"
67 " {-V|--version} }\n"
68 "",
69 bin_name, bin_name, bin_name);
70
71 return 0;
72 }
73
74 #ifndef BPFTOOL_VERSION
75 /* bpftool's major and minor version numbers are aligned on libbpf's. There is
76 * an offset of 6 for the version number, because bpftool's version was higher
77 * than libbpf's when we adopted this scheme. The patch number remains at 0
78 * for now. Set BPFTOOL_VERSION to override.
79 */
80 #define BPFTOOL_MAJOR_VERSION (LIBBPF_MAJOR_VERSION + 6)
81 #define BPFTOOL_MINOR_VERSION LIBBPF_MINOR_VERSION
82 #define BPFTOOL_PATCH_VERSION 0
83 #endif
84
do_version(int argc,char ** argv)85 static int do_version(int argc, char **argv)
86 {
87 #ifdef HAVE_LIBBFD_SUPPORT
88 const bool has_libbfd = true;
89 #else
90 const bool has_libbfd = false;
91 #endif
92 #ifdef BPFTOOL_WITHOUT_SKELETONS
93 const bool has_skeletons = false;
94 #else
95 const bool has_skeletons = true;
96 #endif
97
98 if (json_output) {
99 jsonw_start_object(json_wtr); /* root object */
100
101 jsonw_name(json_wtr, "version");
102 #ifdef BPFTOOL_VERSION
103 jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
104 #else
105 jsonw_printf(json_wtr, "\"%d.%d.%d\"", BPFTOOL_MAJOR_VERSION,
106 BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
107 #endif
108 jsonw_name(json_wtr, "libbpf_version");
109 jsonw_printf(json_wtr, "\"%d.%d\"",
110 libbpf_major_version(), libbpf_minor_version());
111
112 jsonw_name(json_wtr, "features");
113 jsonw_start_object(json_wtr); /* features */
114 jsonw_bool_field(json_wtr, "libbfd", has_libbfd);
115 jsonw_bool_field(json_wtr, "libbpf_strict", !legacy_libbpf);
116 jsonw_bool_field(json_wtr, "skeletons", has_skeletons);
117 jsonw_end_object(json_wtr); /* features */
118
119 jsonw_end_object(json_wtr); /* root object */
120 } else {
121 unsigned int nb_features = 0;
122
123 #ifdef BPFTOOL_VERSION
124 printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
125 #else
126 printf("%s v%d.%d.%d\n", bin_name, BPFTOOL_MAJOR_VERSION,
127 BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
128 #endif
129 printf("using libbpf %s\n", libbpf_version_string());
130 printf("features:");
131 if (has_libbfd) {
132 printf(" libbfd");
133 nb_features++;
134 }
135 if (!legacy_libbpf) {
136 printf("%s libbpf_strict", nb_features++ ? "," : "");
137 nb_features++;
138 }
139 if (has_skeletons)
140 printf("%s skeletons", nb_features++ ? "," : "");
141 printf("\n");
142 }
143 return 0;
144 }
145
cmd_select(const struct cmd * cmds,int argc,char ** argv,int (* help)(int argc,char ** argv))146 int cmd_select(const struct cmd *cmds, int argc, char **argv,
147 int (*help)(int argc, char **argv))
148 {
149 unsigned int i;
150
151 last_argc = argc;
152 last_argv = argv;
153 last_do_help = help;
154
155 if (argc < 1 && cmds[0].func)
156 return cmds[0].func(argc, argv);
157
158 for (i = 0; cmds[i].cmd; i++) {
159 if (is_prefix(*argv, cmds[i].cmd)) {
160 if (!cmds[i].func) {
161 p_err("command '%s' is not supported in bootstrap mode",
162 cmds[i].cmd);
163 return -1;
164 }
165 return cmds[i].func(argc - 1, argv + 1);
166 }
167 }
168
169 help(argc - 1, argv + 1);
170
171 return -1;
172 }
173
is_prefix(const char * pfx,const char * str)174 bool is_prefix(const char *pfx, const char *str)
175 {
176 if (!pfx)
177 return false;
178 if (strlen(str) < strlen(pfx))
179 return false;
180
181 return !memcmp(str, pfx, strlen(pfx));
182 }
183
184 /* Last argument MUST be NULL pointer */
detect_common_prefix(const char * arg,...)185 int detect_common_prefix(const char *arg, ...)
186 {
187 unsigned int count = 0;
188 const char *ref;
189 char msg[256];
190 va_list ap;
191
192 snprintf(msg, sizeof(msg), "ambiguous prefix: '%s' could be '", arg);
193 va_start(ap, arg);
194 while ((ref = va_arg(ap, const char *))) {
195 if (!is_prefix(arg, ref))
196 continue;
197 count++;
198 if (count > 1)
199 strncat(msg, "' or '", sizeof(msg) - strlen(msg) - 1);
200 strncat(msg, ref, sizeof(msg) - strlen(msg) - 1);
201 }
202 va_end(ap);
203 strncat(msg, "'", sizeof(msg) - strlen(msg) - 1);
204
205 if (count >= 2) {
206 p_err("%s", msg);
207 return -1;
208 }
209
210 return 0;
211 }
212
fprint_hex(FILE * f,void * arg,unsigned int n,const char * sep)213 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
214 {
215 unsigned char *data = arg;
216 unsigned int i;
217
218 for (i = 0; i < n; i++) {
219 const char *pfx = "";
220
221 if (!i)
222 /* nothing */;
223 else if (!(i % 16))
224 fprintf(f, "\n");
225 else if (!(i % 8))
226 fprintf(f, " ");
227 else
228 pfx = sep;
229
230 fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
231 }
232 }
233
234 /* Split command line into argument vector. */
make_args(char * line,char * n_argv[],int maxargs,int cmd_nb)235 static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
236 {
237 static const char ws[] = " \t\r\n";
238 char *cp = line;
239 int n_argc = 0;
240
241 while (*cp) {
242 /* Skip leading whitespace. */
243 cp += strspn(cp, ws);
244
245 if (*cp == '\0')
246 break;
247
248 if (n_argc >= (maxargs - 1)) {
249 p_err("too many arguments to command %d", cmd_nb);
250 return -1;
251 }
252
253 /* Word begins with quote. */
254 if (*cp == '\'' || *cp == '"') {
255 char quote = *cp++;
256
257 n_argv[n_argc++] = cp;
258 /* Find ending quote. */
259 cp = strchr(cp, quote);
260 if (!cp) {
261 p_err("unterminated quoted string in command %d",
262 cmd_nb);
263 return -1;
264 }
265 } else {
266 n_argv[n_argc++] = cp;
267
268 /* Find end of word. */
269 cp += strcspn(cp, ws);
270 if (*cp == '\0')
271 break;
272 }
273
274 /* Separate words. */
275 *cp++ = 0;
276 }
277 n_argv[n_argc] = NULL;
278
279 return n_argc;
280 }
281
282 static int do_batch(int argc, char **argv);
283
284 static const struct cmd cmds[] = {
285 { "help", do_help },
286 { "batch", do_batch },
287 { "prog", do_prog },
288 { "map", do_map },
289 { "link", do_link },
290 { "cgroup", do_cgroup },
291 { "perf", do_perf },
292 { "net", do_net },
293 { "feature", do_feature },
294 { "btf", do_btf },
295 { "gen", do_gen },
296 { "struct_ops", do_struct_ops },
297 { "iter", do_iter },
298 { "version", do_version },
299 { 0 }
300 };
301
do_batch(int argc,char ** argv)302 static int do_batch(int argc, char **argv)
303 {
304 char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
305 char *n_argv[BATCH_ARG_NB_MAX];
306 unsigned int lines = 0;
307 int n_argc;
308 FILE *fp;
309 char *cp;
310 int err = 0;
311 int i;
312
313 if (argc < 2) {
314 p_err("too few parameters for batch");
315 return -1;
316 } else if (!is_prefix(*argv, "file")) {
317 p_err("expected 'file', got: %s", *argv);
318 return -1;
319 } else if (argc > 2) {
320 p_err("too many parameters for batch");
321 return -1;
322 }
323 NEXT_ARG();
324
325 if (!strcmp(*argv, "-"))
326 fp = stdin;
327 else
328 fp = fopen(*argv, "r");
329 if (!fp) {
330 p_err("Can't open file (%s): %s", *argv, strerror(errno));
331 return -1;
332 }
333
334 if (json_output)
335 jsonw_start_array(json_wtr);
336 while (fgets(buf, sizeof(buf), fp)) {
337 cp = strchr(buf, '#');
338 if (cp)
339 *cp = '\0';
340
341 if (strlen(buf) == sizeof(buf) - 1) {
342 errno = E2BIG;
343 break;
344 }
345
346 /* Append continuation lines if any (coming after a line ending
347 * with '\' in the batch file).
348 */
349 while ((cp = strstr(buf, "\\\n")) != NULL) {
350 if (!fgets(contline, sizeof(contline), fp) ||
351 strlen(contline) == 0) {
352 p_err("missing continuation line on command %d",
353 lines);
354 err = -1;
355 goto err_close;
356 }
357
358 cp = strchr(contline, '#');
359 if (cp)
360 *cp = '\0';
361
362 if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
363 p_err("command %d is too long", lines);
364 err = -1;
365 goto err_close;
366 }
367 buf[strlen(buf) - 2] = '\0';
368 strcat(buf, contline);
369 }
370
371 n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
372 if (!n_argc)
373 continue;
374 if (n_argc < 0) {
375 err = n_argc;
376 goto err_close;
377 }
378
379 if (json_output) {
380 jsonw_start_object(json_wtr);
381 jsonw_name(json_wtr, "command");
382 jsonw_start_array(json_wtr);
383 for (i = 0; i < n_argc; i++)
384 jsonw_string(json_wtr, n_argv[i]);
385 jsonw_end_array(json_wtr);
386 jsonw_name(json_wtr, "output");
387 }
388
389 err = cmd_select(cmds, n_argc, n_argv, do_help);
390
391 if (json_output)
392 jsonw_end_object(json_wtr);
393
394 if (err)
395 goto err_close;
396
397 lines++;
398 }
399
400 if (errno && errno != ENOENT) {
401 p_err("reading batch file failed: %s", strerror(errno));
402 err = -1;
403 } else {
404 if (!json_output)
405 printf("processed %d commands\n", lines);
406 }
407 err_close:
408 if (fp != stdin)
409 fclose(fp);
410
411 if (json_output)
412 jsonw_end_array(json_wtr);
413
414 return err;
415 }
416
main(int argc,char ** argv)417 int main(int argc, char **argv)
418 {
419 static const struct option options[] = {
420 { "json", no_argument, NULL, 'j' },
421 { "help", no_argument, NULL, 'h' },
422 { "pretty", no_argument, NULL, 'p' },
423 { "version", no_argument, NULL, 'V' },
424 { "bpffs", no_argument, NULL, 'f' },
425 { "mapcompat", no_argument, NULL, 'm' },
426 { "nomount", no_argument, NULL, 'n' },
427 { "debug", no_argument, NULL, 'd' },
428 { "use-loader", no_argument, NULL, 'L' },
429 { "base-btf", required_argument, NULL, 'B' },
430 { "legacy", no_argument, NULL, 'l' },
431 { 0 }
432 };
433 bool version_requested = false;
434 int opt, ret;
435
436 setlinebuf(stdout);
437
438 #ifdef USE_LIBCAP
439 /* Libcap < 2.63 hooks before main() to compute the number of
440 * capabilities of the running kernel, and doing so it calls prctl()
441 * which may fail and set errno to non-zero.
442 * Let's reset errno to make sure this does not interfere with the
443 * batch mode.
444 */
445 errno = 0;
446 #endif
447
448 last_do_help = do_help;
449 pretty_output = false;
450 json_output = false;
451 show_pinned = false;
452 block_mount = false;
453 bin_name = argv[0];
454
455 opterr = 0;
456 while ((opt = getopt_long(argc, argv, "VhpjfLmndB:l",
457 options, NULL)) >= 0) {
458 switch (opt) {
459 case 'V':
460 version_requested = true;
461 break;
462 case 'h':
463 return do_help(argc, argv);
464 case 'p':
465 pretty_output = true;
466 /* fall through */
467 case 'j':
468 if (!json_output) {
469 json_wtr = jsonw_new(stdout);
470 if (!json_wtr) {
471 p_err("failed to create JSON writer");
472 return -1;
473 }
474 json_output = true;
475 }
476 jsonw_pretty(json_wtr, pretty_output);
477 break;
478 case 'f':
479 show_pinned = true;
480 break;
481 case 'm':
482 relaxed_maps = true;
483 break;
484 case 'n':
485 block_mount = true;
486 break;
487 case 'd':
488 libbpf_set_print(print_all_levels);
489 verifier_logs = true;
490 break;
491 case 'B':
492 base_btf = btf__parse(optarg, NULL);
493 if (libbpf_get_error(base_btf)) {
494 p_err("failed to parse base BTF at '%s': %ld\n",
495 optarg, libbpf_get_error(base_btf));
496 base_btf = NULL;
497 return -1;
498 }
499 break;
500 case 'L':
501 use_loader = true;
502 break;
503 case 'l':
504 legacy_libbpf = true;
505 break;
506 default:
507 p_err("unrecognized option '%s'", argv[optind - 1]);
508 if (json_output)
509 clean_and_exit(-1);
510 else
511 usage();
512 }
513 }
514
515 if (!legacy_libbpf) {
516 /* Allow legacy map definitions for skeleton generation.
517 * It will still be rejected if users use LIBBPF_STRICT_ALL
518 * mode for loading generated skeleton.
519 */
520 libbpf_set_strict_mode(LIBBPF_STRICT_ALL & ~LIBBPF_STRICT_MAP_DEFINITIONS);
521 }
522
523 argc -= optind;
524 argv += optind;
525 if (argc < 0)
526 usage();
527
528 if (version_requested)
529 return do_version(argc, argv);
530
531 ret = cmd_select(cmds, argc, argv, do_help);
532
533 if (json_output)
534 jsonw_destroy(&json_wtr);
535
536 btf__free(base_btf);
537
538 return ret;
539 }
540