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 struct btf *base_btf;
35 struct hashmap *refs_table;
36
clean_and_exit(int i)37 static void __noreturn clean_and_exit(int i)
38 {
39 if (json_output)
40 jsonw_destroy(&json_wtr);
41
42 exit(i);
43 }
44
usage(void)45 void usage(void)
46 {
47 last_do_help(last_argc - 1, last_argv + 1);
48
49 clean_and_exit(-1);
50 }
51
do_help(int argc,char ** argv)52 static int do_help(int argc, char **argv)
53 {
54 if (json_output) {
55 jsonw_null(json_wtr);
56 return 0;
57 }
58
59 fprintf(stderr,
60 "Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
61 " %s batch file FILE\n"
62 " %s version\n"
63 "\n"
64 " OBJECT := { prog | map | link | cgroup | perf | net | feature | btf | gen | struct_ops | iter }\n"
65 " " HELP_SPEC_OPTIONS " |\n"
66 " {-V|--version} }\n"
67 "",
68 bin_name, bin_name, bin_name);
69
70 return 0;
71 }
72
73 static int do_batch(int argc, char **argv);
74 static int do_version(int argc, char **argv);
75
76 static const struct cmd commands[] = {
77 { "help", do_help },
78 { "batch", do_batch },
79 { "prog", do_prog },
80 { "map", do_map },
81 { "link", do_link },
82 { "cgroup", do_cgroup },
83 { "perf", do_perf },
84 { "net", do_net },
85 { "feature", do_feature },
86 { "btf", do_btf },
87 { "gen", do_gen },
88 { "struct_ops", do_struct_ops },
89 { "iter", do_iter },
90 { "version", do_version },
91 { 0 }
92 };
93
94 #ifndef BPFTOOL_VERSION
95 /* bpftool's major and minor version numbers are aligned on libbpf's. There is
96 * an offset of 6 for the version number, because bpftool's version was higher
97 * than libbpf's when we adopted this scheme. The patch number remains at 0
98 * for now. Set BPFTOOL_VERSION to override.
99 */
100 #define BPFTOOL_MAJOR_VERSION (LIBBPF_MAJOR_VERSION + 6)
101 #define BPFTOOL_MINOR_VERSION LIBBPF_MINOR_VERSION
102 #define BPFTOOL_PATCH_VERSION 0
103 #endif
104
105 static void
print_feature(const char * feature,bool state,unsigned int * nb_features)106 print_feature(const char *feature, bool state, unsigned int *nb_features)
107 {
108 if (state) {
109 printf("%s %s", *nb_features ? "," : "", feature);
110 *nb_features = *nb_features + 1;
111 }
112 }
113
do_version(int argc,char ** argv)114 static int do_version(int argc, char **argv)
115 {
116 #ifdef HAVE_LIBBFD_SUPPORT
117 const bool has_libbfd = true;
118 #else
119 const bool has_libbfd = false;
120 #endif
121 #ifdef HAVE_LLVM_SUPPORT
122 const bool has_llvm = true;
123 #else
124 const bool has_llvm = false;
125 #endif
126 #ifdef BPFTOOL_WITHOUT_SKELETONS
127 const bool has_skeletons = false;
128 #else
129 const bool has_skeletons = true;
130 #endif
131 bool bootstrap = false;
132 int i;
133
134 for (i = 0; commands[i].cmd; i++) {
135 if (!strcmp(commands[i].cmd, "prog")) {
136 /* Assume we run a bootstrap version if "bpftool prog"
137 * is not available.
138 */
139 bootstrap = !commands[i].func;
140 break;
141 }
142 }
143
144 if (json_output) {
145 jsonw_start_object(json_wtr); /* root object */
146
147 jsonw_name(json_wtr, "version");
148 #ifdef BPFTOOL_VERSION
149 jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
150 #else
151 jsonw_printf(json_wtr, "\"%d.%d.%d\"", BPFTOOL_MAJOR_VERSION,
152 BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
153 #endif
154 jsonw_name(json_wtr, "libbpf_version");
155 jsonw_printf(json_wtr, "\"%u.%u\"",
156 libbpf_major_version(), libbpf_minor_version());
157
158 jsonw_name(json_wtr, "features");
159 jsonw_start_object(json_wtr); /* features */
160 jsonw_bool_field(json_wtr, "libbfd", has_libbfd);
161 jsonw_bool_field(json_wtr, "llvm", has_llvm);
162 jsonw_bool_field(json_wtr, "skeletons", has_skeletons);
163 jsonw_bool_field(json_wtr, "bootstrap", bootstrap);
164 jsonw_end_object(json_wtr); /* features */
165
166 jsonw_end_object(json_wtr); /* root object */
167 } else {
168 unsigned int nb_features = 0;
169
170 #ifdef BPFTOOL_VERSION
171 printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
172 #else
173 printf("%s v%d.%d.%d\n", bin_name, BPFTOOL_MAJOR_VERSION,
174 BPFTOOL_MINOR_VERSION, BPFTOOL_PATCH_VERSION);
175 #endif
176 printf("using libbpf %s\n", libbpf_version_string());
177 printf("features:");
178 print_feature("libbfd", has_libbfd, &nb_features);
179 print_feature("llvm", has_llvm, &nb_features);
180 print_feature("skeletons", has_skeletons, &nb_features);
181 print_feature("bootstrap", bootstrap, &nb_features);
182 printf("\n");
183 }
184 return 0;
185 }
186
cmd_select(const struct cmd * cmds,int argc,char ** argv,int (* help)(int argc,char ** argv))187 int cmd_select(const struct cmd *cmds, int argc, char **argv,
188 int (*help)(int argc, char **argv))
189 {
190 unsigned int i;
191
192 last_argc = argc;
193 last_argv = argv;
194 last_do_help = help;
195
196 if (argc < 1 && cmds[0].func)
197 return cmds[0].func(argc, argv);
198
199 for (i = 0; cmds[i].cmd; i++) {
200 if (is_prefix(*argv, cmds[i].cmd)) {
201 if (!cmds[i].func) {
202 p_err("command '%s' is not supported in bootstrap mode",
203 cmds[i].cmd);
204 return -1;
205 }
206 return cmds[i].func(argc - 1, argv + 1);
207 }
208 }
209
210 help(argc - 1, argv + 1);
211
212 return -1;
213 }
214
is_prefix(const char * pfx,const char * str)215 bool is_prefix(const char *pfx, const char *str)
216 {
217 if (!pfx)
218 return false;
219 if (strlen(str) < strlen(pfx))
220 return false;
221
222 return !memcmp(str, pfx, strlen(pfx));
223 }
224
225 /* Last argument MUST be NULL pointer */
detect_common_prefix(const char * arg,...)226 int detect_common_prefix(const char *arg, ...)
227 {
228 unsigned int count = 0;
229 const char *ref;
230 char msg[256];
231 va_list ap;
232
233 snprintf(msg, sizeof(msg), "ambiguous prefix: '%s' could be '", arg);
234 va_start(ap, arg);
235 while ((ref = va_arg(ap, const char *))) {
236 if (!is_prefix(arg, ref))
237 continue;
238 count++;
239 if (count > 1)
240 strncat(msg, "' or '", sizeof(msg) - strlen(msg) - 1);
241 strncat(msg, ref, sizeof(msg) - strlen(msg) - 1);
242 }
243 va_end(ap);
244 strncat(msg, "'", sizeof(msg) - strlen(msg) - 1);
245
246 if (count >= 2) {
247 p_err("%s", msg);
248 return -1;
249 }
250
251 return 0;
252 }
253
fprint_hex(FILE * f,void * arg,unsigned int n,const char * sep)254 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
255 {
256 unsigned char *data = arg;
257 unsigned int i;
258
259 for (i = 0; i < n; i++) {
260 const char *pfx = "";
261
262 if (!i)
263 /* nothing */;
264 else if (!(i % 16))
265 fprintf(f, "\n");
266 else if (!(i % 8))
267 fprintf(f, " ");
268 else
269 pfx = sep;
270
271 fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
272 }
273 }
274
275 /* Split command line into argument vector. */
make_args(char * line,char * n_argv[],int maxargs,int cmd_nb)276 static int make_args(char *line, char *n_argv[], int maxargs, int cmd_nb)
277 {
278 static const char ws[] = " \t\r\n";
279 char *cp = line;
280 int n_argc = 0;
281
282 while (*cp) {
283 /* Skip leading whitespace. */
284 cp += strspn(cp, ws);
285
286 if (*cp == '\0')
287 break;
288
289 if (n_argc >= (maxargs - 1)) {
290 p_err("too many arguments to command %d", cmd_nb);
291 return -1;
292 }
293
294 /* Word begins with quote. */
295 if (*cp == '\'' || *cp == '"') {
296 char quote = *cp++;
297
298 n_argv[n_argc++] = cp;
299 /* Find ending quote. */
300 cp = strchr(cp, quote);
301 if (!cp) {
302 p_err("unterminated quoted string in command %d",
303 cmd_nb);
304 return -1;
305 }
306 } else {
307 n_argv[n_argc++] = cp;
308
309 /* Find end of word. */
310 cp += strcspn(cp, ws);
311 if (*cp == '\0')
312 break;
313 }
314
315 /* Separate words. */
316 *cp++ = 0;
317 }
318 n_argv[n_argc] = NULL;
319
320 return n_argc;
321 }
322
do_batch(int argc,char ** argv)323 static int do_batch(int argc, char **argv)
324 {
325 char buf[BATCH_LINE_LEN_MAX], contline[BATCH_LINE_LEN_MAX];
326 char *n_argv[BATCH_ARG_NB_MAX];
327 unsigned int lines = 0;
328 int n_argc;
329 FILE *fp;
330 char *cp;
331 int err = 0;
332 int i;
333
334 if (argc < 2) {
335 p_err("too few parameters for batch");
336 return -1;
337 } else if (argc > 2) {
338 p_err("too many parameters for batch");
339 return -1;
340 } else if (!is_prefix(*argv, "file")) {
341 p_err("expected 'file', got: %s", *argv);
342 return -1;
343 }
344 NEXT_ARG();
345
346 if (!strcmp(*argv, "-"))
347 fp = stdin;
348 else
349 fp = fopen(*argv, "r");
350 if (!fp) {
351 p_err("Can't open file (%s): %s", *argv, strerror(errno));
352 return -1;
353 }
354
355 if (json_output)
356 jsonw_start_array(json_wtr);
357 while (fgets(buf, sizeof(buf), fp)) {
358 cp = strchr(buf, '#');
359 if (cp)
360 *cp = '\0';
361
362 if (strlen(buf) == sizeof(buf) - 1) {
363 errno = E2BIG;
364 break;
365 }
366
367 /* Append continuation lines if any (coming after a line ending
368 * with '\' in the batch file).
369 */
370 while ((cp = strstr(buf, "\\\n")) != NULL) {
371 if (!fgets(contline, sizeof(contline), fp) ||
372 strlen(contline) == 0) {
373 p_err("missing continuation line on command %u",
374 lines);
375 err = -1;
376 goto err_close;
377 }
378
379 cp = strchr(contline, '#');
380 if (cp)
381 *cp = '\0';
382
383 if (strlen(buf) + strlen(contline) + 1 > sizeof(buf)) {
384 p_err("command %u is too long", lines);
385 err = -1;
386 goto err_close;
387 }
388 buf[strlen(buf) - 2] = '\0';
389 strcat(buf, contline);
390 }
391
392 n_argc = make_args(buf, n_argv, BATCH_ARG_NB_MAX, lines);
393 if (!n_argc)
394 continue;
395 if (n_argc < 0) {
396 err = n_argc;
397 goto err_close;
398 }
399
400 if (json_output) {
401 jsonw_start_object(json_wtr);
402 jsonw_name(json_wtr, "command");
403 jsonw_start_array(json_wtr);
404 for (i = 0; i < n_argc; i++)
405 jsonw_string(json_wtr, n_argv[i]);
406 jsonw_end_array(json_wtr);
407 jsonw_name(json_wtr, "output");
408 }
409
410 err = cmd_select(commands, n_argc, n_argv, do_help);
411
412 if (json_output)
413 jsonw_end_object(json_wtr);
414
415 if (err)
416 goto err_close;
417
418 lines++;
419 }
420
421 if (errno && errno != ENOENT) {
422 p_err("reading batch file failed: %s", strerror(errno));
423 err = -1;
424 } else {
425 if (!json_output)
426 printf("processed %u commands\n", lines);
427 }
428 err_close:
429 if (fp != stdin)
430 fclose(fp);
431
432 if (json_output)
433 jsonw_end_array(json_wtr);
434
435 return err;
436 }
437
main(int argc,char ** argv)438 int main(int argc, char **argv)
439 {
440 static const struct option options[] = {
441 { "json", no_argument, NULL, 'j' },
442 { "help", no_argument, NULL, 'h' },
443 { "pretty", no_argument, NULL, 'p' },
444 { "version", no_argument, NULL, 'V' },
445 { "bpffs", no_argument, NULL, 'f' },
446 { "mapcompat", no_argument, NULL, 'm' },
447 { "nomount", no_argument, NULL, 'n' },
448 { "debug", no_argument, NULL, 'd' },
449 { "use-loader", no_argument, NULL, 'L' },
450 { "base-btf", required_argument, NULL, 'B' },
451 { 0 }
452 };
453 bool version_requested = false;
454 int opt, ret;
455
456 setlinebuf(stdout);
457
458 #ifdef USE_LIBCAP
459 /* Libcap < 2.63 hooks before main() to compute the number of
460 * capabilities of the running kernel, and doing so it calls prctl()
461 * which may fail and set errno to non-zero.
462 * Let's reset errno to make sure this does not interfere with the
463 * batch mode.
464 */
465 errno = 0;
466 #endif
467
468 last_do_help = do_help;
469 pretty_output = false;
470 json_output = false;
471 show_pinned = false;
472 block_mount = false;
473 bin_name = "bpftool";
474
475 opterr = 0;
476 while ((opt = getopt_long(argc, argv, "VhpjfLmndB:l",
477 options, NULL)) >= 0) {
478 switch (opt) {
479 case 'V':
480 version_requested = true;
481 break;
482 case 'h':
483 return do_help(argc, argv);
484 case 'p':
485 pretty_output = true;
486 /* fall through */
487 case 'j':
488 if (!json_output) {
489 json_wtr = jsonw_new(stdout);
490 if (!json_wtr) {
491 p_err("failed to create JSON writer");
492 return -1;
493 }
494 json_output = true;
495 }
496 jsonw_pretty(json_wtr, pretty_output);
497 break;
498 case 'f':
499 show_pinned = true;
500 break;
501 case 'm':
502 relaxed_maps = true;
503 break;
504 case 'n':
505 block_mount = true;
506 break;
507 case 'd':
508 libbpf_set_print(print_all_levels);
509 verifier_logs = true;
510 break;
511 case 'B':
512 base_btf = btf__parse(optarg, NULL);
513 if (!base_btf) {
514 p_err("failed to parse base BTF at '%s': %d\n",
515 optarg, -errno);
516 return -1;
517 }
518 break;
519 case 'L':
520 use_loader = true;
521 break;
522 default:
523 p_err("unrecognized option '%s'", argv[optind - 1]);
524 if (json_output)
525 clean_and_exit(-1);
526 else
527 usage();
528 }
529 }
530
531 argc -= optind;
532 argv += optind;
533 if (argc < 0)
534 usage();
535
536 if (version_requested)
537 return do_version(argc, argv);
538
539 ret = cmd_select(commands, argc, argv, do_help);
540
541 if (json_output)
542 jsonw_destroy(&json_wtr);
543
544 btf__free(base_btf);
545
546 return ret;
547 }
548