tools/bpf/bpftool/main.c

   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
  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
  42 void usage(void)
  43 {
  44         last_do_help(last_argc - 1, last_argv + 1);
  45
  46         clean_and_exit(-1);
  47 }
  48
  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
  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)
  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
  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
 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 */
 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(msg);
 143                 return -1;
 144         }
 145
 146         return 0;
 147 }
 148
 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. */
 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
 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                         goto err_close;
 308
 309                 if (json_output) {
 310                         jsonw_start_object(json_wtr);
 311                         jsonw_name(json_wtr, "command");
 312                         jsonw_start_array(json_wtr);
 313                         for (i = 0; i < n_argc; i++)
 314                                 jsonw_string(json_wtr, n_argv[i]);
 315                         jsonw_end_array(json_wtr);
 316                         jsonw_name(json_wtr, "output");
 317                 }
 318
 319                 err = cmd_select(cmds, n_argc, n_argv, do_help);
 320
 321                 if (json_output)
 322                         jsonw_end_object(json_wtr);
 323
 324                 if (err)
 325                         goto err_close;
 326
 327                 lines++;
 328         }
 329
 330         if (errno && errno != ENOENT) {
 331                 p_err("reading batch file failed: %s", strerror(errno));
 332                 err = -1;
 333         } else {
 334                 if (!json_output)
 335                         printf("processed %d commands\n", lines);
 336                 err = 0;
 337         }
 338 err_close:
 339         if (fp != stdin)
 340                 fclose(fp);
 341
 342         if (json_output)
 343                 jsonw_end_array(json_wtr);
 344
 345         return err;
 346 }
 347
 348 int main(int argc, char **argv)
 349 {
 350         static const struct option options[] = {
 351                 { "json",       no_argument,    NULL,   'j' },
 352                 { "help",       no_argument,    NULL,   'h' },
 353                 { "pretty",     no_argument,    NULL,   'p' },
 354                 { "version",    no_argument,    NULL,   'V' },
 355                 { "bpffs",      no_argument,    NULL,   'f' },
 356                 { "mapcompat",  no_argument,    NULL,   'm' },
 357                 { "nomount",    no_argument,    NULL,   'n' },
 358                 { "debug",      no_argument,    NULL,   'd' },
 359                 { 0 }
 360         };
 361         int opt, ret;
 362
 363         last_do_help = do_help;
 364         pretty_output = false;
 365         json_output = false;
 366         show_pinned = false;
 367         block_mount = false;
 368         bin_name = argv[0];
 369
 370         hash_init(prog_table.table);
 371         hash_init(map_table.table);
 372
 373         opterr = 0;
 374         while ((opt = getopt_long(argc, argv, "Vhpjfmnd",
 375                                   options, NULL)) >= 0) {
 376                 switch (opt) {
 377                 case 'V':
 378                         return do_version(argc, argv);
 379                 case 'h':
 380                         return do_help(argc, argv);
 381                 case 'p':
 382                         pretty_output = true;
 383                         /* fall through */
 384                 case 'j':
 385                         if (!json_output) {
 386                                 json_wtr = jsonw_new(stdout);
 387                                 if (!json_wtr) {
 388                                         p_err("failed to create JSON writer");
 389                                         return -1;
 390                                 }
 391                                 json_output = true;
 392                         }
 393                         jsonw_pretty(json_wtr, pretty_output);
 394                         break;
 395                 case 'f':
 396                         show_pinned = true;
 397                         break;
 398                 case 'm':
 399                         bpf_flags = MAPS_RELAX_COMPAT;
 400                         break;
 401                 case 'n':
 402                         block_mount = true;
 403                         break;
 404                 case 'd':
 405                         libbpf_set_print(print_all_levels);
 406                         verifier_logs = true;
 407                         break;
 408                 default:
 409                         p_err("unrecognized option '%s'", argv[optind - 1]);
 410                         if (json_output)
 411                                 clean_and_exit(-1);
 412                         else
 413                                 usage();
 414                 }
 415         }
 416
 417         argc -= optind;
 418         argv += optind;
 419         if (argc < 0)
 420                 usage();
 421
 422         ret = cmd_select(cmds, argc, argv, do_help);
 423
 424         if (json_output)
 425                 jsonw_destroy(&json_wtr);
 426
 427         if (show_pinned) {
 428                 delete_pinned_obj_table(&prog_table);
 429                 delete_pinned_obj_table(&map_table);
 430         }
 431
 432         return ret;
 433 }