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