tools/bpf/bpftool/main.c

   1 /*
   2  * Copyright (C) 2017 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 /* Author: Jakub Kicinski <kubakici@wp.pl> */
  35
  36 #include <bfd.h>
  37 #include <ctype.h>
  38 #include <errno.h>
  39 #include <getopt.h>
  40 #include <linux/bpf.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44
  45 #include <bpf.h>
  46
  47 #include "main.h"
  48
  49 const char *bin_name;
  50 static int last_argc;
  51 static char **last_argv;
  52 static int (*last_do_help)(int argc, char **argv);
  53 json_writer_t *json_wtr;
  54 bool pretty_output;
  55 bool json_output;
  56 bool show_pinned;
  57 struct pinned_obj_table prog_table;
  58 struct pinned_obj_table map_table;
  59
  60 static void __noreturn clean_and_exit(int i)
  61 {
  62         if (json_output)
  63                 jsonw_destroy(&json_wtr);
  64
  65         exit(i);
  66 }
  67
  68 void usage(void)
  69 {
  70         last_do_help(last_argc - 1, last_argv + 1);
  71
  72         clean_and_exit(-1);
  73 }
  74
  75 static int do_help(int argc, char **argv)
  76 {
  77         if (json_output) {
  78                 jsonw_null(json_wtr);
  79                 return 0;
  80         }
  81
  82         fprintf(stderr,
  83                 "Usage: %s [OPTIONS] OBJECT { COMMAND | help }\n"
  84                 "       %s batch file FILE\n"
  85                 "       %s version\n"
  86                 "\n"
  87                 "       OBJECT := { prog | map | cgroup }\n"
  88                 "       " HELP_SPEC_OPTIONS "\n"
  89                 "",
  90                 bin_name, bin_name, bin_name);
  91
  92         return 0;
  93 }
  94
  95 static int do_version(int argc, char **argv)
  96 {
  97         if (json_output) {
  98                 jsonw_start_object(json_wtr);
  99                 jsonw_name(json_wtr, "version");
 100                 jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
 101                 jsonw_end_object(json_wtr);
 102         } else {
 103                 printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
 104         }
 105         return 0;
 106 }
 107
 108 int cmd_select(const struct cmd *cmds, int argc, char **argv,
 109                int (*help)(int argc, char **argv))
 110 {
 111         unsigned int i;
 112
 113         last_argc = argc;
 114         last_argv = argv;
 115         last_do_help = help;
 116
 117         if (argc < 1 && cmds[0].func)
 118                 return cmds[0].func(argc, argv);
 119
 120         for (i = 0; cmds[i].func; i++)
 121                 if (is_prefix(*argv, cmds[i].cmd))
 122                         return cmds[i].func(argc - 1, argv + 1);
 123
 124         help(argc - 1, argv + 1);
 125
 126         return -1;
 127 }
 128
 129 bool is_prefix(const char *pfx, const char *str)
 130 {
 131         if (!pfx)
 132                 return false;
 133         if (strlen(str) < strlen(pfx))
 134                 return false;
 135
 136         return !memcmp(str, pfx, strlen(pfx));
 137 }
 138
 139 void fprint_hex(FILE *f, void *arg, unsigned int n, const char *sep)
 140 {
 141         unsigned char *data = arg;
 142         unsigned int i;
 143
 144         for (i = 0; i < n; i++) {
 145                 const char *pfx = "";
 146
 147                 if (!i)
 148                         /* nothing */;
 149                 else if (!(i % 16))
 150                         fprintf(f, "\n");
 151                 else if (!(i % 8))
 152                         fprintf(f, "  ");
 153                 else
 154                         pfx = sep;
 155
 156                 fprintf(f, "%s%02hhx", i ? pfx : "", data[i]);
 157         }
 158 }
 159
 160 static int do_batch(int argc, char **argv);
 161
 162 static const struct cmd cmds[] = {
 163         { "help",       do_help },
 164         { "batch",      do_batch },
 165         { "prog",       do_prog },
 166         { "map",        do_map },
 167         { "cgroup",     do_cgroup },
 168         { "version",    do_version },
 169         { 0 }
 170 };
 171
 172 static int do_batch(int argc, char **argv)
 173 {
 174         unsigned int lines = 0;
 175         char *n_argv[4096];
 176         char buf[65536];
 177         int n_argc;
 178         FILE *fp;
 179         int err;
 180         int i;
 181
 182         if (argc < 2) {
 183                 p_err("too few parameters for batch");
 184                 return -1;
 185         } else if (!is_prefix(*argv, "file")) {
 186                 p_err("expected 'file', got: %s", *argv);
 187                 return -1;
 188         } else if (argc > 2) {
 189                 p_err("too many parameters for batch");
 190                 return -1;
 191         }
 192         NEXT_ARG();
 193
 194         fp = fopen(*argv, "r");
 195         if (!fp) {
 196                 p_err("Can't open file (%s): %s", *argv, strerror(errno));
 197                 return -1;
 198         }
 199
 200         if (json_output)
 201                 jsonw_start_array(json_wtr);
 202         while (fgets(buf, sizeof(buf), fp)) {
 203                 if (strlen(buf) == sizeof(buf) - 1) {
 204                         errno = E2BIG;
 205                         break;
 206                 }
 207
 208                 n_argc = 0;
 209                 n_argv[n_argc] = strtok(buf, " \t\n");
 210
 211                 while (n_argv[n_argc]) {
 212                         n_argc++;
 213                         if (n_argc == ARRAY_SIZE(n_argv)) {
 214                                 p_err("line %d has too many arguments, skip",
 215                                       lines);
 216                                 n_argc = 0;
 217                                 break;
 218                         }
 219                         n_argv[n_argc] = strtok(NULL, " \t\n");
 220                 }
 221
 222                 if (!n_argc)
 223                         continue;
 224
 225                 if (json_output) {
 226                         jsonw_start_object(json_wtr);
 227                         jsonw_name(json_wtr, "command");
 228                         jsonw_start_array(json_wtr);
 229                         for (i = 0; i < n_argc; i++)
 230                                 jsonw_string(json_wtr, n_argv[i]);
 231                         jsonw_end_array(json_wtr);
 232                         jsonw_name(json_wtr, "output");
 233                 }
 234
 235                 err = cmd_select(cmds, n_argc, n_argv, do_help);
 236
 237                 if (json_output)
 238                         jsonw_end_object(json_wtr);
 239
 240                 if (err)
 241                         goto err_close;
 242
 243                 lines++;
 244         }
 245
 246         if (errno && errno != ENOENT) {
 247                 p_err("reading batch file failed: %s", strerror(errno));
 248                 err = -1;
 249         } else {
 250                 p_info("processed %d lines", lines);
 251                 err = 0;
 252         }
 253 err_close:
 254         fclose(fp);
 255
 256         if (json_output)
 257                 jsonw_end_array(json_wtr);
 258
 259         return err;
 260 }
 261
 262 int main(int argc, char **argv)
 263 {
 264         static const struct option options[] = {
 265                 { "json",       no_argument,    NULL,   'j' },
 266                 { "help",       no_argument,    NULL,   'h' },
 267                 { "pretty",     no_argument,    NULL,   'p' },
 268                 { "version",    no_argument,    NULL,   'V' },
 269                 { "bpffs",      no_argument,    NULL,   'f' },
 270                 { 0 }
 271         };
 272         int opt, ret;
 273
 274         last_do_help = do_help;
 275         pretty_output = false;
 276         json_output = false;
 277         show_pinned = false;
 278         bin_name = argv[0];
 279
 280         hash_init(prog_table.table);
 281         hash_init(map_table.table);
 282
 283         opterr = 0;
 284         while ((opt = getopt_long(argc, argv, "Vhpjf",
 285                                   options, NULL)) >= 0) {
 286                 switch (opt) {
 287                 case 'V':
 288                         return do_version(argc, argv);
 289                 case 'h':
 290                         return do_help(argc, argv);
 291                 case 'p':
 292                         pretty_output = true;
 293                         /* fall through */
 294                 case 'j':
 295                         if (!json_output) {
 296                                 json_wtr = jsonw_new(stdout);
 297                                 if (!json_wtr) {
 298                                         p_err("failed to create JSON writer");
 299                                         return -1;
 300                                 }
 301                                 json_output = true;
 302                         }
 303                         jsonw_pretty(json_wtr, pretty_output);
 304                         break;
 305                 case 'f':
 306                         show_pinned = true;
 307                         break;
 308                 default:
 309                         p_err("unrecognized option '%s'", argv[optind - 1]);
 310                         if (json_output)
 311                                 clean_and_exit(-1);
 312                         else
 313                                 usage();
 314                 }
 315         }
 316
 317         argc -= optind;
 318         argv += optind;
 319         if (argc < 0)
 320                 usage();
 321
 322         bfd_init();
 323
 324         ret = cmd_select(cmds, argc, argv, do_help);
 325
 326         if (json_output)
 327                 jsonw_destroy(&json_wtr);
 328
 329         if (show_pinned) {
 330                 delete_pinned_obj_table(&prog_table);
 331                 delete_pinned_obj_table(&map_table);
 332         }
 333
 334         return ret;
 335 }