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