bfdd/bfdd.c

   1 /*
   2  * BFD daemon code
   3  * Copyright (C) 2018 Network Device Education Foundation, Inc. ("NetDEF")
   4  *
   5  * FRR is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License as published by the
   7  * Free Software Foundation; either version 2, or (at your option) any
   8  * later version.
   9  *
  10  * FRR is distributed in the hope that it will be useful, but
  11  * WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with FRR; see the file COPYING.  If not, write to the Free
  17  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  18  * 02111-1307, USA.
  19  */
  20
  21 #include <zebra.h>
  22
  23 #include <arpa/inet.h>
  24 #include <netinet/in.h>
  25 #include <sys/socket.h>
  26 #include <sys/un.h>
  27
  28 #include <err.h>
  29
  30 #include "filter.h"
  31 #include "if.h"
  32 #include "vrf.h"
  33
  34 #include "bfd.h"
  35 #include "bfdd_nb.h"
  36 #include "bfddp_packet.h"
  37 #include "lib/version.h"
  38 #include "lib/command.h"
  39
  40
  41 /*
  42  * FRR related code.
  43  */
  44 DEFINE_MGROUP(BFDD, "Bidirectional Forwarding Detection Daemon");
  45 DEFINE_MTYPE(BFDD, BFDD_CONTROL, "long-lived control socket memory");
  46 DEFINE_MTYPE(BFDD, BFDD_NOTIFICATION, "short-lived control notification data");
  47
  48 /* Master of threads. */
  49 struct thread_master *master;
  50
  51 /* BFDd privileges */
  52 static zebra_capabilities_t _caps_p[] = {ZCAP_BIND, ZCAP_SYS_ADMIN, ZCAP_NET_RAW};
  53
  54 /* BFD daemon information. */
  55 static struct frr_daemon_info bfdd_di;
  56
  57 void socket_close(int *s)
  58 {
  59         if (*s <= 0)
  60                 return;
  61
  62         if (close(*s) != 0)
  63                 zlog_err("%s: close(%d): (%d) %s", __func__, *s, errno,
  64                          strerror(errno));
  65
  66         *s = -1;
  67 }
  68
  69 static void sigusr1_handler(void)
  70 {
  71         zlog_rotate();
  72 }
  73
  74 static void sigterm_handler(void)
  75 {
  76         bglobal.bg_shutdown = true;
  77
  78         /* Signalize shutdown. */
  79         frr_early_fini();
  80
  81         /* Stop receiving message from zebra. */
  82         bfdd_zclient_stop();
  83
  84         /* Shutdown controller to avoid receiving anymore commands. */
  85         control_shutdown();
  86
  87         /* Shutdown and free all protocol related memory. */
  88         bfd_shutdown();
  89
  90         bfd_vrf_terminate();
  91
  92         /* Terminate and free() FRR related memory. */
  93         frr_fini();
  94
  95         exit(0);
  96 }
  97
  98 static void sighup_handler(void)
  99 {
 100         zlog_info("SIGHUP received");
 101
 102         /* Reload config file. */
 103         vty_read_config(NULL, bfdd_di.config_file, config_default);
 104 }
 105
 106 static struct frr_signal_t bfd_signals[] = {
 107         {
 108                 .signal = SIGUSR1,
 109                 .handler = &sigusr1_handler,
 110         },
 111         {
 112                 .signal = SIGTERM,
 113                 .handler = &sigterm_handler,
 114         },
 115         {
 116                 .signal = SIGINT,
 117                 .handler = &sigterm_handler,
 118         },
 119         {
 120                 .signal = SIGHUP,
 121                 .handler = &sighup_handler,
 122         },
 123 };
 124
 125 static const struct frr_yang_module_info *const bfdd_yang_modules[] = {
 126         &frr_filter_info,
 127         &frr_interface_info,
 128         &frr_bfdd_info,
 129         &frr_vrf_info,
 130 };
 131
 132 FRR_DAEMON_INFO(bfdd, BFD, .vty_port = 2617,
 133                 .proghelp = "Implementation of the BFD protocol.",
 134                 .signals = bfd_signals, .n_signals = array_size(bfd_signals),
 135                 .privs = &bglobal.bfdd_privs,
 136                 .yang_modules = bfdd_yang_modules,
 137                 .n_yang_modules = array_size(bfdd_yang_modules),
 138 );
 139
 140 #define OPTION_CTLSOCK 1001
 141 #define OPTION_DPLANEADDR 2000
 142 static const struct option longopts[] = {
 143         {"bfdctl", required_argument, NULL, OPTION_CTLSOCK},
 144         {"dplaneaddr", required_argument, NULL, OPTION_DPLANEADDR},
 145         {0}
 146 };
 147
 148
 149 /*
 150  * BFD daemon related code.
 151  */
 152 struct bfd_global bglobal;
 153
 154 const struct bfd_diag_str_list diag_list[] = {
 155         {.str = "control-expired", .type = BD_CONTROL_EXPIRED},
 156         {.str = "echo-failed", .type = BD_ECHO_FAILED},
 157         {.str = "neighbor-down", .type = BD_NEIGHBOR_DOWN},
 158         {.str = "forwarding-reset", .type = BD_FORWARDING_RESET},
 159         {.str = "path-down", .type = BD_PATH_DOWN},
 160         {.str = "concatenated-path-down", .type = BD_CONCATPATH_DOWN},
 161         {.str = "administratively-down", .type = BD_ADMIN_DOWN},
 162         {.str = "reverse-concat-path-down", .type = BD_REVCONCATPATH_DOWN},
 163         {.str = NULL},
 164 };
 165
 166 const struct bfd_state_str_list state_list[] = {
 167         {.str = "admin-down", .type = PTM_BFD_ADM_DOWN},
 168         {.str = "down", .type = PTM_BFD_DOWN},
 169         {.str = "init", .type = PTM_BFD_INIT},
 170         {.str = "up", .type = PTM_BFD_UP},
 171         {.str = NULL},
 172 };
 173
 174 static uint16_t
 175 parse_port(const char *str)
 176 {
 177         char *nulbyte;
 178         long rv;
 179
 180         errno = 0;
 181         rv = strtol(str, &nulbyte, 10);
 182         /* No conversion performed. */
 183         if (rv == 0 && errno == EINVAL) {
 184                 fprintf(stderr, "invalid BFD data plane address port: %s\n",
 185                         str);
 186                 exit(0);
 187         }
 188         /* Invalid number range. */
 189         if ((rv <= 0 || rv >= 65535) || errno == ERANGE) {
 190                 fprintf(stderr, "invalid BFD data plane port range: %s\n",
 191                         str);
 192                 exit(0);
 193         }
 194         /* There was garbage at the end of the string. */
 195         if (*nulbyte != 0) {
 196                 fprintf(stderr, "invalid BFD data plane port: %s\n",
 197                         str);
 198                 exit(0);
 199         }
 200
 201         return (uint16_t)rv;
 202 }
 203
 204 static void
 205 distributed_bfd_init(const char *arg)
 206 {
 207         char *sptr, *saux;
 208         bool is_client = false;
 209         size_t slen;
 210         socklen_t salen;
 211         char addr[64];
 212         char type[64];
 213         union {
 214                 struct sockaddr_in sin;
 215                 struct sockaddr_in6 sin6;
 216                 struct sockaddr_un sun;
 217         } sa;
 218
 219         /* Basic parsing: find ':' to figure out type part and address part. */
 220         sptr = strchr(arg, ':');
 221         if (sptr == NULL) {
 222                 fprintf(stderr, "invalid BFD data plane socket: %s\n", arg);
 223                 exit(1);
 224         }
 225
 226         /* Calculate type string length. */
 227         slen = (size_t)(sptr - arg);
 228
 229         /* Copy the address part. */
 230         sptr++;
 231         strlcpy(addr, sptr, sizeof(addr));
 232
 233         /* Copy type part. */
 234         strlcpy(type, arg, slen + 1);
 235
 236         /* Reset address data. */
 237         memset(&sa, 0, sizeof(sa));
 238
 239         /* Fill the address information. */
 240         if (strcmp(type, "unix") == 0 || strcmp(type, "unixc") == 0) {
 241                 if (strcmp(type, "unixc") == 0)
 242                         is_client = true;
 243
 244                 salen = sizeof(sa.sun);
 245                 sa.sun.sun_family = AF_UNIX;
 246                 strlcpy(sa.sun.sun_path, addr, sizeof(sa.sun.sun_path));
 247         } else if (strcmp(type, "ipv4") == 0 || strcmp(type, "ipv4c") == 0) {
 248                 if (strcmp(type, "ipv4c") == 0)
 249                         is_client = true;
 250
 251                 salen = sizeof(sa.sin);
 252                 sa.sin.sin_family = AF_INET;
 253
 254                 /* Parse port if any. */
 255                 sptr = strchr(addr, ':');
 256                 if (sptr == NULL) {
 257                         sa.sin.sin_port = htons(BFD_DATA_PLANE_DEFAULT_PORT);
 258                 } else {
 259                         *sptr = 0;
 260                         sa.sin.sin_port = htons(parse_port(sptr + 1));
 261                 }
 262
 263                 if (inet_pton(AF_INET, addr, &sa.sin.sin_addr) != 1)
 264                         errx(1, "%s: inet_pton: invalid address %s", __func__,
 265                              addr);
 266         } else if (strcmp(type, "ipv6") == 0 || strcmp(type, "ipv6c") == 0) {
 267                 if (strcmp(type, "ipv6c") == 0)
 268                         is_client = true;
 269
 270                 salen = sizeof(sa.sin6);
 271                 sa.sin6.sin6_family = AF_INET6;
 272
 273                 /* Check for IPv6 enclosures '[]' */
 274                 sptr = &addr[0];
 275                 if (*sptr != '[')
 276                         errx(1, "%s: invalid IPv6 address format: %s", __func__,
 277                              addr);
 278
 279                 saux = strrchr(addr, ']');
 280                 if (saux == NULL)
 281                         errx(1, "%s: invalid IPv6 address format: %s", __func__,
 282                              addr);
 283
 284                 /* Consume the '[]:' part. */
 285                 slen = saux - sptr;
 286                 memmove(addr, addr + 1, slen);
 287                 addr[slen - 1] = 0;
 288
 289                 /* Parse port if any. */
 290                 saux++;
 291                 sptr = strrchr(saux, ':');
 292                 if (sptr == NULL) {
 293                         sa.sin6.sin6_port = htons(BFD_DATA_PLANE_DEFAULT_PORT);
 294                 } else {
 295                         *sptr = 0;
 296                         sa.sin6.sin6_port = htons(parse_port(sptr + 1));
 297                 }
 298
 299                 if (inet_pton(AF_INET6, addr, &sa.sin6.sin6_addr) != 1)
 300                         errx(1, "%s: inet_pton: invalid address %s", __func__,
 301                              addr);
 302         } else {
 303                 fprintf(stderr, "invalid BFD data plane socket type: %s\n",
 304                         type);
 305                 exit(1);
 306         }
 307
 308         /* Initialize BFD data plane listening socket. */
 309         bfd_dplane_init((struct sockaddr *)&sa, salen, is_client);
 310 }
 311
 312 static void bg_init(void)
 313 {
 314         struct zebra_privs_t bfdd_privs = {
 315 #if defined(FRR_USER) && defined(FRR_GROUP)
 316                 .user = FRR_USER,
 317                 .group = FRR_GROUP,
 318 #endif
 319 #if defined(VTY_GROUP)
 320                 .vty_group = VTY_GROUP,
 321 #endif
 322                 .caps_p = _caps_p,
 323                 .cap_num_p = array_size(_caps_p),
 324                 .cap_num_i = 0,
 325         };
 326
 327         TAILQ_INIT(&bglobal.bg_bcslist);
 328         TAILQ_INIT(&bglobal.bg_obslist);
 329
 330         memcpy(&bglobal.bfdd_privs, &bfdd_privs,
 331                sizeof(bfdd_privs));
 332 }
 333
 334 int main(int argc, char *argv[])
 335 {
 336         char ctl_path[512], dplane_addr[512];
 337         bool ctlsockused = false;
 338         int opt;
 339
 340         bglobal.bg_use_dplane = false;
 341
 342         /* Initialize system sockets. */
 343         bg_init();
 344
 345         frr_preinit(&bfdd_di, argc, argv);
 346         frr_opt_add("", longopts,
 347                     "      --bfdctl       Specify bfdd control socket\n"
 348                     "      --dplaneaddr   Specify BFD data plane address\n");
 349
 350         snprintf(ctl_path, sizeof(ctl_path), BFDD_CONTROL_SOCKET,
 351                  "", "");
 352         while (true) {
 353                 opt = frr_getopt(argc, argv, NULL);
 354                 if (opt == EOF)
 355                         break;
 356
 357                 switch (opt) {
 358                 case OPTION_CTLSOCK:
 359                         strlcpy(ctl_path, optarg, sizeof(ctl_path));
 360                         ctlsockused = true;
 361                         break;
 362                 case OPTION_DPLANEADDR:
 363                         strlcpy(dplane_addr, optarg, sizeof(dplane_addr));
 364                         bglobal.bg_use_dplane = true;
 365                         break;
 366
 367                 default:
 368                         frr_help_exit(1);
 369                 }
 370         }
 371
 372         if (bfdd_di.pathspace && !ctlsockused)
 373                 snprintf(ctl_path, sizeof(ctl_path), BFDD_CONTROL_SOCKET,
 374                          "/", bfdd_di.pathspace);
 375
 376         /* Initialize FRR infrastructure. */
 377         master = frr_init();
 378
 379         /* Initialize control socket. */
 380         control_init(ctl_path);
 381
 382         /* Initialize BFD data structures. */
 383         bfd_initialize();
 384
 385         bfd_vrf_init();
 386
 387         access_list_init();
 388
 389         /* Initialize zebra connection. */
 390         bfdd_zclient_init(&bglobal.bfdd_privs);
 391
 392         thread_add_read(master, control_accept, NULL, bglobal.bg_csock,
 393                         &bglobal.bg_csockev);
 394
 395         /* Install commands. */
 396         bfdd_vty_init();
 397
 398         /* read configuration file and daemonize  */
 399         frr_config_fork();
 400
 401         /* Initialize BFD data plane listening socket. */
 402         if (bglobal.bg_use_dplane)
 403                 distributed_bfd_init(dplane_addr);
 404
 405         frr_run(master);
 406         /* NOTREACHED */
 407
 408         return 0;
 409 }