lib/libfrr.c

   1 /*
   2  * libfrr overall management functions
   3  *
   4  * Copyright (C) 2016  David Lamparter for NetDEF, Inc.
   5  *
   6  * This program is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License as published by the Free
   8  * Software Foundation; either version 2 of the License, or (at your option)
   9  * any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  14  * more details.
  15  *
  16  * You should have received a copy of the GNU General Public License along
  17  * with this program; see the file COPYING; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20
  21 #include <zebra.h>
  22 #include <sys/un.h>
  23
  24 #include <sys/types.h>
  25 #include <sys/wait.h>
  26
  27 #include "libfrr.h"
  28 #include "getopt.h"
  29 #include "privs.h"
  30 #include "vty.h"
  31 #include "command.h"
  32 #include "lib/version.h"
  33 #include "lib_vty.h"
  34 #include "log_vty.h"
  35 #include "zclient.h"
  36 #include "module.h"
  37 #include "network.h"
  38 #include "lib_errors.h"
  39 #include "db.h"
  40 #include "northbound_cli.h"
  41 #include "northbound_db.h"
  42 #include "debug.h"
  43 #include "frrcu.h"
  44 #include "frr_pthread.h"
  45 #include "defaults.h"
  46 #include "frrscript.h"
  47
  48 DEFINE_HOOK(frr_late_init, (struct thread_master * tm), (tm));
  49 DEFINE_HOOK(frr_config_pre, (struct thread_master * tm), (tm));
  50 DEFINE_HOOK(frr_config_post, (struct thread_master * tm), (tm));
  51 DEFINE_KOOH(frr_early_fini, (), ());
  52 DEFINE_KOOH(frr_fini, (), ());
  53
  54 const char frr_sysconfdir[] = SYSCONFDIR;
  55 char frr_vtydir[256];
  56 #ifdef HAVE_SQLITE3
  57 const char frr_dbdir[] = DAEMON_DB_DIR;
  58 #endif
  59 const char frr_moduledir[] = MODULE_PATH;
  60 const char frr_scriptdir[] = SCRIPT_PATH;
  61
  62 char frr_protoname[256] = "NONE";
  63 char frr_protonameinst[256] = "NONE";
  64
  65 char config_default[512];
  66 char frr_zclientpath[256];
  67 static char pidfile_default[1024];
  68 #ifdef HAVE_SQLITE3
  69 static char dbfile_default[512];
  70 #endif
  71 static char vtypath_default[512];
  72
  73 bool debug_memstats_at_exit = false;
  74 static bool nodetach_term, nodetach_daemon;
  75 static uint64_t startup_fds;
  76
  77 static char comb_optstr[256];
  78 static struct option comb_lo[64];
  79 static struct option *comb_next_lo = &comb_lo[0];
  80 static char comb_helpstr[4096];
  81
  82 struct optspec {
  83         const char *optstr;
  84         const char *helpstr;
  85         const struct option *longopts;
  86 };
  87
  88 static void opt_extend(const struct optspec *os)
  89 {
  90         const struct option *lo;
  91
  92         strlcat(comb_optstr, os->optstr, sizeof(comb_optstr));
  93         strlcat(comb_helpstr, os->helpstr, sizeof(comb_helpstr));
  94         for (lo = os->longopts; lo->name; lo++)
  95                 memcpy(comb_next_lo++, lo, sizeof(*lo));
  96 }
  97
  98
  99 #define OPTION_VTYSOCK   1000
 100 #define OPTION_MODULEDIR 1002
 101 #define OPTION_LOG       1003
 102 #define OPTION_LOGLEVEL  1004
 103 #define OPTION_TCLI      1005
 104 #define OPTION_DB_FILE   1006
 105 #define OPTION_LOGGING   1007
 106 #define OPTION_LIMIT_FDS 1008
 107 #define OPTION_SCRIPTDIR 1009
 108
 109 static const struct option lo_always[] = {
 110         {"help", no_argument, NULL, 'h'},
 111         {"version", no_argument, NULL, 'v'},
 112         {"daemon", no_argument, NULL, 'd'},
 113         {"module", no_argument, NULL, 'M'},
 114         {"profile", required_argument, NULL, 'F'},
 115         {"pathspace", required_argument, NULL, 'N'},
 116         {"vty_socket", required_argument, NULL, OPTION_VTYSOCK},
 117         {"moduledir", required_argument, NULL, OPTION_MODULEDIR},
 118         {"scriptdir", required_argument, NULL, OPTION_SCRIPTDIR},
 119         {"log", required_argument, NULL, OPTION_LOG},
 120         {"log-level", required_argument, NULL, OPTION_LOGLEVEL},
 121         {"tcli", no_argument, NULL, OPTION_TCLI},
 122         {"command-log-always", no_argument, NULL, OPTION_LOGGING},
 123         {"limit-fds", required_argument, NULL, OPTION_LIMIT_FDS},
 124         {NULL}};
 125 static const struct optspec os_always = {
 126         "hvdM:F:N:",
 127         "  -h, --help         Display this help and exit\n"
 128         "  -v, --version      Print program version\n"
 129         "  -d, --daemon       Runs in daemon mode\n"
 130         "  -M, --module       Load specified module\n"
 131         "  -F, --profile      Use specified configuration profile\n"
 132         "  -N, --pathspace    Insert prefix into config & socket paths\n"
 133         "      --vty_socket   Override vty socket path\n"
 134         "      --moduledir    Override modules directory\n"
 135         "      --scriptdir    Override scripts directory\n"
 136         "      --log          Set Logging to stdout, syslog, or file:<name>\n"
 137         "      --log-level    Set Logging Level to use, debug, info, warn, etc\n"
 138         "      --tcli         Use transaction-based CLI\n"
 139         "      --limit-fds    Limit number of fds supported\n",
 140         lo_always};
 141
 142
 143 static const struct option lo_cfg_pid_dry[] = {
 144         {"pid_file", required_argument, NULL, 'i'},
 145         {"config_file", required_argument, NULL, 'f'},
 146 #ifdef HAVE_SQLITE3
 147         {"db_file", required_argument, NULL, OPTION_DB_FILE},
 148 #endif
 149         {"dryrun", no_argument, NULL, 'C'},
 150         {"terminal", no_argument, NULL, 't'},
 151         {NULL}};
 152 static const struct optspec os_cfg_pid_dry = {
 153         "f:i:Ct",
 154         "  -f, --config_file  Set configuration file name\n"
 155         "  -i, --pid_file     Set process identifier file name\n"
 156 #ifdef HAVE_SQLITE3
 157         "      --db_file      Set database file name\n"
 158 #endif
 159         "  -C, --dryrun       Check configuration for validity and exit\n"
 160         "  -t, --terminal     Open terminal session on stdio\n"
 161         "  -d -t              Daemonize after terminal session ends\n",
 162         lo_cfg_pid_dry};
 163
 164
 165 static const struct option lo_zclient[] = {
 166         {"socket", required_argument, NULL, 'z'},
 167         {NULL}};
 168 static const struct optspec os_zclient = {
 169         "z:", "  -z, --socket       Set path of zebra socket\n", lo_zclient};
 170
 171
 172 static const struct option lo_vty[] = {
 173         {"vty_addr", required_argument, NULL, 'A'},
 174         {"vty_port", required_argument, NULL, 'P'},
 175         {NULL}};
 176 static const struct optspec os_vty = {
 177         "A:P:",
 178         "  -A, --vty_addr     Set vty's bind address\n"
 179         "  -P, --vty_port     Set vty's port number\n",
 180         lo_vty};
 181
 182
 183 static const struct option lo_user[] = {{"user", required_argument, NULL, 'u'},
 184                                         {"group", required_argument, NULL, 'g'},
 185                                         {NULL}};
 186 static const struct optspec os_user = {"u:g:",
 187                                        "  -u, --user         User to run as\n"
 188                                        "  -g, --group        Group to run as\n",
 189                                        lo_user};
 190
 191 bool frr_zclient_addr(struct sockaddr_storage *sa, socklen_t *sa_len,
 192                       const char *path)
 193 {
 194         memset(sa, 0, sizeof(*sa));
 195
 196         if (!path)
 197                 path = frr_zclientpath;
 198
 199         if (!strncmp(path, ZAPI_TCP_PATHNAME, strlen(ZAPI_TCP_PATHNAME))) {
 200                 /* note: this functionality is disabled at bottom */
 201                 int af;
 202                 int port = ZEBRA_PORT;
 203                 char *err = NULL;
 204                 struct sockaddr_in *sin = NULL;
 205                 struct sockaddr_in6 *sin6 = NULL;
 206
 207                 path += strlen(ZAPI_TCP_PATHNAME);
 208
 209                 switch (path[0]) {
 210                 case '4':
 211                         path++;
 212                         af = AF_INET;
 213                         break;
 214                 case '6':
 215                         path++;
 216                 /* fallthrough */
 217                 default:
 218                         af = AF_INET6;
 219                         break;
 220                 }
 221
 222                 switch (path[0]) {
 223                 case '\0':
 224                         break;
 225                 case ':':
 226                         path++;
 227                         port = strtoul(path, &err, 10);
 228                         if (*err || !*path)
 229                                 return false;
 230                         break;
 231                 default:
 232                         return false;
 233                 }
 234
 235                 sa->ss_family = af;
 236                 switch (af) {
 237                 case AF_INET:
 238                         sin = (struct sockaddr_in *)sa;
 239                         sin->sin_port = htons(port);
 240                         sin->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
 241                         *sa_len = sizeof(struct sockaddr_in);
 242 #ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
 243                         sin->sin_len = *sa_len;
 244 #endif
 245                         break;
 246                 case AF_INET6:
 247                         sin6 = (struct sockaddr_in6 *)sa;
 248                         sin6->sin6_port = htons(port);
 249                         inet_pton(AF_INET6, "::1", &sin6->sin6_addr);
 250                         *sa_len = sizeof(struct sockaddr_in6);
 251 #ifdef SIN6_LEN
 252                         sin6->sin6_len = *sa_len;
 253 #endif
 254                         break;
 255                 }
 256
 257 #if 1
 258                 /* force-disable this path, because tcp-zebra is a
 259                  * SECURITY ISSUE.  there are no checks at all against
 260                  * untrusted users on the local system connecting on TCP
 261                  * and injecting bogus routing data into the entire routing
 262                  * domain.
 263                  *
 264                  * The functionality is only left here because it may be
 265                  * useful during development, in order to be able to get
 266                  * tcpdump or wireshark watching ZAPI as TCP.  If you want
 267                  * to do that, flip the #if 1 above to #if 0. */
 268                 memset(sa, 0, sizeof(*sa));
 269                 return false;
 270 #endif
 271         } else {
 272                 /* "sun" is a #define on solaris */
 273                 struct sockaddr_un *suna = (struct sockaddr_un *)sa;
 274
 275                 suna->sun_family = AF_UNIX;
 276                 strlcpy(suna->sun_path, path, sizeof(suna->sun_path));
 277 #ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
 278                 *sa_len = suna->sun_len = SUN_LEN(suna);
 279 #else
 280                 *sa_len = sizeof(suna->sun_family) + strlen(suna->sun_path);
 281 #endif /* HAVE_STRUCT_SOCKADDR_UN_SUN_LEN */
 282 #if 0
 283                 /* this is left here for future reference;  Linux abstract
 284                  * socket namespace support can be enabled by replacing
 285                  * above #if 0 with #ifdef GNU_LINUX.
 286                  *
 287                  * THIS IS A SECURITY ISSUE, the abstract socket namespace
 288                  * does not have user/group permission control on sockets.
 289                  * we'd need to implement SCM_CREDENTIALS support first to
 290                  * check that only proper users can connect to abstract
 291                  * sockets. (same problem as tcp-zebra, except there is a
 292                  * fix with SCM_CREDENTIALS.  tcp-zebra has no such fix.)
 293                  */
 294                 if (suna->sun_path[0] == '@')
 295                         suna->sun_path[0] = '\0';
 296 #endif
 297         }
 298         return true;
 299 }
 300
 301 static struct frr_daemon_info *di = NULL;
 302
 303 void frr_init_vtydir(void)
 304 {
 305         snprintf(frr_vtydir, sizeof(frr_vtydir), DAEMON_VTY_DIR, "", "");
 306 }
 307
 308 void frr_preinit(struct frr_daemon_info *daemon, int argc, char **argv)
 309 {
 310         di = daemon;
 311
 312         /* basename(), opencoded. */
 313         char *p = strrchr(argv[0], '/');
 314         di->progname = p ? p + 1 : argv[0];
 315
 316         umask(0027);
 317
 318         opt_extend(&os_always);
 319         if (!(di->flags & FRR_NO_CFG_PID_DRY))
 320                 opt_extend(&os_cfg_pid_dry);
 321         if (!(di->flags & FRR_NO_PRIVSEP))
 322                 opt_extend(&os_user);
 323         if (!(di->flags & FRR_NO_ZCLIENT))
 324                 opt_extend(&os_zclient);
 325         if (!(di->flags & FRR_NO_TCPVTY))
 326                 opt_extend(&os_vty);
 327         if (di->flags & FRR_DETACH_LATER)
 328                 nodetach_daemon = true;
 329
 330         frr_init_vtydir();
 331         snprintf(config_default, sizeof(config_default), "%s/%s.conf",
 332                  frr_sysconfdir, di->name);
 333         snprintf(pidfile_default, sizeof(pidfile_default), "%s/%s.pid",
 334                  frr_vtydir, di->name);
 335         snprintf(frr_zclientpath, sizeof(frr_zclientpath),
 336                  ZEBRA_SERV_PATH, "", "");
 337 #ifdef HAVE_SQLITE3
 338         snprintf(dbfile_default, sizeof(dbfile_default), "%s/%s.db",
 339                  frr_dbdir, di->name);
 340 #endif
 341
 342         strlcpy(frr_protoname, di->logname, sizeof(frr_protoname));
 343         strlcpy(frr_protonameinst, di->logname, sizeof(frr_protonameinst));
 344
 345         di->cli_mode = FRR_CLI_CLASSIC;
 346
 347         /* we may be starting with extra FDs open for whatever purpose,
 348          * e.g. logging, some module, etc.  Recording them here allows later
 349          * checking whether an fd is valid for such extension purposes,
 350          * without this we could end up e.g. logging to a BGP session fd.
 351          */
 352         startup_fds = 0;
 353         for (int i = 0; i < 64; i++) {
 354                 struct stat st;
 355
 356                 if (fstat(i, &st))
 357                         continue;
 358                 if (S_ISDIR(st.st_mode) || S_ISBLK(st.st_mode))
 359                         continue;
 360
 361                 startup_fds |= UINT64_C(0x1) << (uint64_t)i;
 362         }
 363 }
 364
 365 bool frr_is_startup_fd(int fd)
 366 {
 367         return !!(startup_fds & (UINT64_C(0x1) << (uint64_t)fd));
 368 }
 369
 370 void frr_opt_add(const char *optstr, const struct option *longopts,
 371                  const char *helpstr)
 372 {
 373         const struct optspec main_opts = {optstr, helpstr, longopts};
 374         opt_extend(&main_opts);
 375 }
 376
 377 void frr_help_exit(int status)
 378 {
 379         FILE *target = status ? stderr : stdout;
 380
 381         if (status != 0)
 382                 fprintf(stderr, "Invalid options.\n\n");
 383
 384         if (di->printhelp)
 385                 di->printhelp(target);
 386         else
 387                 fprintf(target, "Usage: %s [OPTION...]\n\n%s%s%s\n\n%s",
 388                         di->progname, di->proghelp, di->copyright ? "\n\n" : "",
 389                         di->copyright ? di->copyright : "", comb_helpstr);
 390         fprintf(target, "\nReport bugs to %s\n", FRR_BUG_ADDRESS);
 391         exit(status);
 392 }
 393
 394 struct option_chain {
 395         struct option_chain *next;
 396         const char *arg;
 397 };
 398
 399 static struct option_chain *modules = NULL, **modnext = &modules;
 400 static int errors = 0;
 401
 402 static int frr_opt(int opt)
 403 {
 404         static int vty_port_set = 0;
 405         static int vty_addr_set = 0;
 406         struct option_chain *oc;
 407         char *err;
 408
 409         switch (opt) {
 410         case 'h':
 411                 frr_help_exit(0);
 412                 break;
 413         case 'v':
 414                 print_version(di->progname);
 415                 exit(0);
 416                 break;
 417         case 'd':
 418                 di->daemon_mode = true;
 419                 break;
 420         case 'M':
 421                 oc = XMALLOC(MTYPE_TMP, sizeof(*oc));
 422                 oc->arg = optarg;
 423                 oc->next = NULL;
 424                 *modnext = oc;
 425                 modnext = &oc->next;
 426                 break;
 427         case 'F':
 428                 if (!frr_defaults_profile_valid(optarg)) {
 429                         const char **p;
 430                         FILE *ofd = stderr;
 431
 432                         if (!strcmp(optarg, "help"))
 433                                 ofd = stdout;
 434                         else
 435                                 fprintf(stderr,
 436                                         "The \"%s\" configuration profile is not valid for this FRR version.\n",
 437                                         optarg);
 438
 439                         fprintf(ofd, "Available profiles are:\n");
 440                         for (p = frr_defaults_profiles; *p; p++)
 441                                 fprintf(ofd, "%s%s\n",
 442                                         strcmp(*p, DFLT_NAME) ? "   " : " * ",
 443                                         *p);
 444
 445                         if (ofd == stdout)
 446                                 exit(0);
 447                         fprintf(ofd, "\n");
 448                         errors++;
 449                         break;
 450                 }
 451                 frr_defaults_profile_set(optarg);
 452                 break;
 453         case 'i':
 454                 if (di->flags & FRR_NO_CFG_PID_DRY)
 455                         return 1;
 456                 di->pid_file = optarg;
 457                 break;
 458         case 'f':
 459                 if (di->flags & FRR_NO_CFG_PID_DRY)
 460                         return 1;
 461                 di->config_file = optarg;
 462                 break;
 463         case 'N':
 464                 if (di->pathspace) {
 465                         fprintf(stderr,
 466                                 "-N/--pathspace option specified more than once!\n");
 467                         errors++;
 468                         break;
 469                 }
 470                 if (di->zpathspace)
 471                         fprintf(stderr,
 472                                 "-N option overridden by -z for zebra named socket path\n");
 473
 474                 if (strchr(optarg, '/') || strchr(optarg, '.')) {
 475                         fprintf(stderr,
 476                                 "slashes or dots are not permitted in the --pathspace option.\n");
 477                         errors++;
 478                         break;
 479                 }
 480                 di->pathspace = optarg;
 481
 482                 if (!di->zpathspace)
 483                         snprintf(frr_zclientpath, sizeof(frr_zclientpath),
 484                                  ZEBRA_SERV_PATH, "/", di->pathspace);
 485                 snprintf(frr_vtydir, sizeof(frr_vtydir), DAEMON_VTY_DIR, "/",
 486                          di->pathspace);
 487                 snprintf(pidfile_default, sizeof(pidfile_default), "%s/%s.pid",
 488                          frr_vtydir, di->name);
 489                 break;
 490 #ifdef HAVE_SQLITE3
 491         case OPTION_DB_FILE:
 492                 if (di->flags & FRR_NO_CFG_PID_DRY)
 493                         return 1;
 494                 di->db_file = optarg;
 495                 break;
 496 #endif
 497         case 'C':
 498                 if (di->flags & FRR_NO_CFG_PID_DRY)
 499                         return 1;
 500                 di->dryrun = true;
 501                 break;
 502         case 't':
 503                 if (di->flags & FRR_NO_CFG_PID_DRY)
 504                         return 1;
 505                 di->terminal = true;
 506                 break;
 507         case 'z':
 508                 di->zpathspace = true;
 509                 if (di->pathspace)
 510                         fprintf(stderr,
 511                                 "-z option overrides -N option for zebra named socket path\n");
 512                 if (di->flags & FRR_NO_ZCLIENT)
 513                         return 1;
 514                 strlcpy(frr_zclientpath, optarg, sizeof(frr_zclientpath));
 515                 break;
 516         case 'A':
 517                 if (di->flags & FRR_NO_TCPVTY)
 518                         return 1;
 519                 if (vty_addr_set) {
 520                         fprintf(stderr,
 521                                 "-A option specified more than once!\n");
 522                         errors++;
 523                         break;
 524                 }
 525                 vty_addr_set = 1;
 526                 di->vty_addr = optarg;
 527                 break;
 528         case 'P':
 529                 if (di->flags & FRR_NO_TCPVTY)
 530                         return 1;
 531                 if (vty_port_set) {
 532                         fprintf(stderr,
 533                                 "-P option specified more than once!\n");
 534                         errors++;
 535                         break;
 536                 }
 537                 vty_port_set = 1;
 538                 di->vty_port = strtoul(optarg, &err, 0);
 539                 if (*err || !*optarg) {
 540                         fprintf(stderr,
 541                                 "invalid port number \"%s\" for -P option\n",
 542                                 optarg);
 543                         errors++;
 544                         break;
 545                 }
 546                 break;
 547         case OPTION_VTYSOCK:
 548                 if (di->vty_sock_path) {
 549                         fprintf(stderr,
 550                                 "--vty_socket option specified more than once!\n");
 551                         errors++;
 552                         break;
 553                 }
 554                 di->vty_sock_path = optarg;
 555                 break;
 556         case OPTION_MODULEDIR:
 557                 if (di->module_path) {
 558                         fprintf(stderr,
 559                                 "----moduledir option specified more than once!\n");
 560                         errors++;
 561                         break;
 562                 }
 563                 di->module_path = optarg;
 564                 break;
 565         case OPTION_SCRIPTDIR:
 566                 if (di->script_path) {
 567                         fprintf(stderr, "--scriptdir option specified more than once!\n");
 568                         errors++;
 569                         break;
 570                 }
 571                 di->script_path = optarg;
 572                 break;
 573         case OPTION_TCLI:
 574                 di->cli_mode = FRR_CLI_TRANSACTIONAL;
 575                 break;
 576         case 'u':
 577                 if (di->flags & FRR_NO_PRIVSEP)
 578                         return 1;
 579                 di->privs->user = optarg;
 580                 break;
 581         case 'g':
 582                 if (di->flags & FRR_NO_PRIVSEP)
 583                         return 1;
 584                 di->privs->group = optarg;
 585                 break;
 586         case OPTION_LOG:
 587                 di->early_logging = optarg;
 588                 break;
 589         case OPTION_LOGLEVEL:
 590                 di->early_loglevel = optarg;
 591                 break;
 592         case OPTION_LOGGING:
 593                 di->log_always = true;
 594                 break;
 595         case OPTION_LIMIT_FDS:
 596                 di->limit_fds = strtoul(optarg, &err, 0);
 597                 break;
 598         default:
 599                 return 1;
 600         }
 601         return 0;
 602 }
 603
 604 int frr_getopt(int argc, char *const argv[], int *longindex)
 605 {
 606         int opt;
 607         int lidx;
 608
 609         comb_next_lo->name = NULL;
 610
 611         do {
 612                 opt = getopt_long(argc, argv, comb_optstr, comb_lo, &lidx);
 613                 if (frr_opt(opt))
 614                         break;
 615         } while (opt != -1);
 616
 617         if (opt == -1 && errors)
 618                 frr_help_exit(1);
 619         if (longindex)
 620                 *longindex = lidx;
 621         return opt;
 622 }
 623
 624 static void frr_mkdir(const char *path, bool strip)
 625 {
 626         char buf[256];
 627         mode_t prev;
 628         int ret;
 629         struct zprivs_ids_t ids;
 630
 631         if (strip) {
 632                 char *slash = strrchr(path, '/');
 633                 size_t plen;
 634                 if (!slash)
 635                         return;
 636                 plen = slash - path;
 637                 if (plen > sizeof(buf) - 1)
 638                         return;
 639                 memcpy(buf, path, plen);
 640                 buf[plen] = '\0';
 641                 path = buf;
 642         }
 643
 644         /* o+rx (..5) is needed for the frrvty group to work properly;
 645          * without it, users in the frrvty group can't access the vty sockets.
 646          */
 647         prev = umask(0022);
 648         ret = mkdir(path, 0755);
 649         umask(prev);
 650
 651         if (ret != 0) {
 652                 /* if EEXIST, return without touching the permissions,
 653                  * so user-set custom permissions are left in place
 654                  */
 655                 if (errno == EEXIST)
 656                         return;
 657
 658                 flog_err(EC_LIB_SYSTEM_CALL, "failed to mkdir \"%s\": %s", path,
 659                          strerror(errno));
 660                 return;
 661         }
 662
 663         zprivs_get_ids(&ids);
 664         if (chown(path, ids.uid_normal, ids.gid_normal))
 665                 flog_err(EC_LIB_SYSTEM_CALL, "failed to chown \"%s\": %s", path,
 666                          strerror(errno));
 667 }
 668
 669 static struct thread_master *master;
 670 struct thread_master *frr_init(void)
 671 {
 672         struct option_chain *oc;
 673         struct frrmod_runtime *module;
 674         struct zprivs_ids_t ids;
 675         char moderr[256];
 676         char p_instance[16] = "", p_pathspace[256] = "";
 677         const char *dir;
 678         dir = di->module_path ? di->module_path : frr_moduledir;
 679
 680         srandom(time(NULL));
 681         frr_defaults_apply();
 682
 683         if (di->instance) {
 684                 snprintf(frr_protonameinst, sizeof(frr_protonameinst), "%s[%u]",
 685                          di->logname, di->instance);
 686                 snprintf(p_instance, sizeof(p_instance), "-%d", di->instance);
 687         }
 688         if (di->pathspace)
 689                 snprintf(p_pathspace, sizeof(p_pathspace), "%s/",
 690                          di->pathspace);
 691
 692         snprintf(config_default, sizeof(config_default), "%s%s%s%s.conf",
 693                  frr_sysconfdir, p_pathspace, di->name, p_instance);
 694         snprintf(pidfile_default, sizeof(pidfile_default), "%s/%s%s.pid",
 695                  frr_vtydir, di->name, p_instance);
 696 #ifdef HAVE_SQLITE3
 697         snprintf(dbfile_default, sizeof(dbfile_default), "%s/%s%s%s.db",
 698                  frr_dbdir, p_pathspace, di->name, p_instance);
 699 #endif
 700
 701         zprivs_preinit(di->privs);
 702         zprivs_get_ids(&ids);
 703
 704         zlog_init(di->progname, di->logname, di->instance,
 705                   ids.uid_normal, ids.gid_normal);
 706
 707         command_setup_early_logging(di->early_logging, di->early_loglevel);
 708
 709         if (!frr_zclient_addr(&zclient_addr, &zclient_addr_len,
 710                               frr_zclientpath)) {
 711                 fprintf(stderr, "Invalid zserv socket path: %s\n",
 712                         frr_zclientpath);
 713                 exit(1);
 714         }
 715
 716         /* don't mkdir these as root... */
 717         if (!(di->flags & FRR_NO_PRIVSEP)) {
 718                 if (!di->pid_file || !di->vty_path)
 719                         frr_mkdir(frr_vtydir, false);
 720                 if (di->pid_file)
 721                         frr_mkdir(di->pid_file, true);
 722                 if (di->vty_path)
 723                         frr_mkdir(di->vty_path, true);
 724         }
 725
 726         frrmod_init(di->module);
 727         while (modules) {
 728                 modules = (oc = modules)->next;
 729                 module = frrmod_load(oc->arg, dir, moderr, sizeof(moderr));
 730                 if (!module) {
 731                         fprintf(stderr, "%s\n", moderr);
 732                         exit(1);
 733                 }
 734                 XFREE(MTYPE_TMP, oc);
 735         }
 736
 737         zprivs_init(di->privs);
 738
 739         master = thread_master_create(NULL);
 740         signal_init(master, di->n_signals, di->signals);
 741
 742 #ifdef HAVE_SQLITE3
 743         if (!di->db_file)
 744                 di->db_file = dbfile_default;
 745         db_init(di->db_file);
 746 #endif
 747
 748         if (di->flags & FRR_LIMITED_CLI)
 749                 cmd_init(-1);
 750         else
 751                 cmd_init(1);
 752
 753         vty_init(master, di->log_always);
 754         lib_cmd_init();
 755
 756         frr_pthread_init();
 757 #ifdef HAVE_SCRIPTING
 758         frrscript_init(di->script_path ? di->script_path : frr_scriptdir);
 759 #endif
 760
 761         log_ref_init();
 762         log_ref_vty_init();
 763         lib_error_init();
 764
 765         yang_init(true);
 766
 767         debug_init_cli();
 768
 769         nb_init(master, di->yang_modules, di->n_yang_modules, true);
 770         if (nb_db_init() != NB_OK)
 771                 flog_warn(EC_LIB_NB_DATABASE,
 772                           "%s: failed to initialize northbound database",
 773                           __func__);
 774
 775         return master;
 776 }
 777
 778 const char *frr_get_progname(void)
 779 {
 780         return di ? di->progname : NULL;
 781 }
 782
 783 enum frr_cli_mode frr_get_cli_mode(void)
 784 {
 785         return di ? di->cli_mode : FRR_CLI_CLASSIC;
 786 }
 787
 788 uint32_t frr_get_fd_limit(void)
 789 {
 790         return di ? di->limit_fds : 0;
 791 }
 792
 793 static int rcvd_signal = 0;
 794
 795 static void rcv_signal(int signum)
 796 {
 797         rcvd_signal = signum;
 798         /* poll() is interrupted by the signal; handled below */
 799 }
 800
 801 static void frr_daemon_wait(int fd)
 802 {
 803         struct pollfd pfd[1];
 804         int ret;
 805         pid_t exitpid;
 806         int exitstat;
 807         sigset_t sigs, prevsigs;
 808
 809         sigemptyset(&sigs);
 810         sigaddset(&sigs, SIGTSTP);
 811         sigaddset(&sigs, SIGQUIT);
 812         sigaddset(&sigs, SIGINT);
 813         sigprocmask(SIG_BLOCK, &sigs, &prevsigs);
 814
 815         struct sigaction sa = {
 816                 .sa_handler = rcv_signal, .sa_flags = SA_RESETHAND,
 817         };
 818         sigemptyset(&sa.sa_mask);
 819         sigaction(SIGTSTP, &sa, NULL);
 820         sigaction(SIGQUIT, &sa, NULL);
 821         sigaction(SIGINT, &sa, NULL);
 822
 823         do {
 824                 char buf[1];
 825                 ssize_t nrecv;
 826
 827                 pfd[0].fd = fd;
 828                 pfd[0].events = POLLIN;
 829
 830                 rcvd_signal = 0;
 831
 832 #if defined(HAVE_PPOLL)
 833                 ret = ppoll(pfd, 1, NULL, &prevsigs);
 834 #elif defined(HAVE_POLLTS)
 835                 ret = pollts(pfd, 1, NULL, &prevsigs);
 836 #else
 837                 /* racy -- only used on FreeBSD 9 */
 838                 sigset_t tmpsigs;
 839                 sigprocmask(SIG_SETMASK, &prevsigs, &tmpsigs);
 840                 ret = poll(pfd, 1, -1);
 841                 sigprocmask(SIG_SETMASK, &tmpsigs, NULL);
 842 #endif
 843                 if (ret < 0 && errno != EINTR && errno != EAGAIN) {
 844                         perror("poll()");
 845                         exit(1);
 846                 }
 847                 switch (rcvd_signal) {
 848                 case SIGTSTP:
 849                         send(fd, "S", 1, 0);
 850                         do {
 851                                 nrecv = recv(fd, buf, sizeof(buf), 0);
 852                         } while (nrecv == -1
 853                                  && (errno == EINTR || errno == EAGAIN));
 854
 855                         raise(SIGTSTP);
 856                         sigaction(SIGTSTP, &sa, NULL);
 857                         send(fd, "R", 1, 0);
 858                         break;
 859                 case SIGINT:
 860                         send(fd, "I", 1, 0);
 861                         break;
 862                 case SIGQUIT:
 863                         send(fd, "Q", 1, 0);
 864                         break;
 865                 }
 866         } while (ret <= 0);
 867
 868         exitpid = waitpid(-1, &exitstat, WNOHANG);
 869         if (exitpid == 0)
 870                 /* child successfully went to main loop & closed socket */
 871                 exit(0);
 872
 873         /* child failed one way or another ... */
 874         if (WIFEXITED(exitstat) && WEXITSTATUS(exitstat) == 0)
 875                 /* can happen in --terminal case if exit is fast enough */
 876                 (void)0;
 877         else if (WIFEXITED(exitstat))
 878                 fprintf(stderr, "%s failed to start, exited %d\n", di->name,
 879                         WEXITSTATUS(exitstat));
 880         else if (WIFSIGNALED(exitstat))
 881                 fprintf(stderr, "%s crashed in startup, signal %d\n", di->name,
 882                         WTERMSIG(exitstat));
 883         else
 884                 fprintf(stderr, "%s failed to start, unknown problem\n",
 885                         di->name);
 886         exit(1);
 887 }
 888
 889 static int daemon_ctl_sock = -1;
 890
 891 static void frr_daemonize(void)
 892 {
 893         int fds[2];
 894         pid_t pid;
 895
 896         if (socketpair(AF_UNIX, SOCK_STREAM, 0, fds)) {
 897                 perror("socketpair() for daemon control");
 898                 exit(1);
 899         }
 900         set_cloexec(fds[0]);
 901         set_cloexec(fds[1]);
 902
 903         pid = fork();
 904         if (pid < 0) {
 905                 perror("fork()");
 906                 exit(1);
 907         }
 908         if (pid == 0) {
 909                 /* child */
 910                 close(fds[0]);
 911                 if (setsid() < 0) {
 912                         perror("setsid()");
 913                         exit(1);
 914                 }
 915
 916                 daemon_ctl_sock = fds[1];
 917                 return;
 918         }
 919
 920         close(fds[1]);
 921         frr_daemon_wait(fds[0]);
 922 }
 923
 924 /*
 925  * Why is this a thread?
 926  *
 927  * The read in of config for integrated config happens *after*
 928  * thread execution starts( because it is passed in via a vtysh -b -n )
 929  * While if you are not using integrated config we want the ability
 930  * to read the config in after thread execution starts, so that
 931  * we can match this behavior.
 932  */
 933 static int frr_config_read_in(struct thread *t)
 934 {
 935         hook_call(frr_config_pre, master);
 936
 937         if (!vty_read_config(vty_shared_candidate_config, di->config_file,
 938                              config_default)
 939             && di->backup_config_file) {
 940                 char *orig = XSTRDUP(MTYPE_TMP, host_config_get());
 941
 942                 zlog_info("Attempting to read backup config file: %s specified",
 943                           di->backup_config_file);
 944                 vty_read_config(vty_shared_candidate_config,
 945                                 di->backup_config_file, config_default);
 946
 947                 host_config_set(orig);
 948                 XFREE(MTYPE_TMP, orig);
 949         }
 950
 951         /*
 952          * Automatically commit the candidate configuration after
 953          * reading the configuration file.
 954          */
 955         if (frr_get_cli_mode() == FRR_CLI_TRANSACTIONAL) {
 956                 struct nb_context context = {};
 957                 char errmsg[BUFSIZ] = {0};
 958                 int ret;
 959
 960                 context.client = NB_CLIENT_CLI;
 961                 ret = nb_candidate_commit(&context, vty_shared_candidate_config,
 962                                           true, "Read configuration file", NULL,
 963                                           errmsg, sizeof(errmsg));
 964                 if (ret != NB_OK && ret != NB_ERR_NO_CHANGES)
 965                         zlog_err(
 966                                 "%s: failed to read configuration file: %s (%s)",
 967                                 __func__, nb_err_name(ret), errmsg);
 968         }
 969
 970         hook_call(frr_config_post, master);
 971
 972         return 0;
 973 }
 974
 975 void frr_config_fork(void)
 976 {
 977         hook_call(frr_late_init, master);
 978
 979         if (!(di->flags & FRR_NO_CFG_PID_DRY)) {
 980                 /* Don't start execution if we are in dry-run mode */
 981                 if (di->dryrun) {
 982                         frr_config_read_in(NULL);
 983                         exit(0);
 984                 }
 985
 986                 thread_add_event(master, frr_config_read_in, NULL, 0,
 987                                  &di->read_in);
 988         }
 989
 990         if (di->daemon_mode || di->terminal)
 991                 frr_daemonize();
 992
 993         if (!di->pid_file)
 994                 di->pid_file = pidfile_default;
 995         pid_output(di->pid_file);
 996         zlog_tls_buffer_init();
 997 }
 998
 999 static void frr_vty_serv(void)
1000 {
1001         /* allow explicit override of vty_path in the future
1002          * (not currently set anywhere) */
1003         if (!di->vty_path) {
1004                 const char *dir;
1005                 char defvtydir[256];
1006
1007                 snprintf(defvtydir, sizeof(defvtydir), "%s", frr_vtydir);
1008
1009                 dir = di->vty_sock_path ? di->vty_sock_path : defvtydir;
1010
1011                 if (di->instance)
1012                         snprintf(vtypath_default, sizeof(vtypath_default),
1013                                  "%s/%s-%d.vty", dir, di->name, di->instance);
1014                 else
1015                         snprintf(vtypath_default, sizeof(vtypath_default),
1016                                  "%s/%s.vty", dir, di->name);
1017
1018                 di->vty_path = vtypath_default;
1019         }
1020
1021         vty_serv_sock(di->vty_addr, di->vty_port, di->vty_path);
1022 }
1023
1024 static void frr_check_detach(void)
1025 {
1026         if (nodetach_term || nodetach_daemon)
1027                 return;
1028
1029         if (daemon_ctl_sock != -1)
1030                 close(daemon_ctl_sock);
1031         daemon_ctl_sock = -1;
1032 }
1033
1034 static void frr_terminal_close(int isexit)
1035 {
1036         int nullfd;
1037
1038         nodetach_term = false;
1039         frr_check_detach();
1040
1041         if (!di->daemon_mode || isexit) {
1042                 printf("\n%s exiting\n", di->name);
1043                 if (!isexit)
1044                         raise(SIGINT);
1045                 return;
1046         } else {
1047                 printf("\n%s daemonizing\n", di->name);
1048                 fflush(stdout);
1049         }
1050
1051         nullfd = open("/dev/null", O_RDONLY | O_NOCTTY);
1052         if (nullfd == -1) {
1053                 flog_err_sys(EC_LIB_SYSTEM_CALL,
1054                              "%s: failed to open /dev/null: %s", __func__,
1055                              safe_strerror(errno));
1056         } else {
1057                 dup2(nullfd, 0);
1058                 dup2(nullfd, 1);
1059                 dup2(nullfd, 2);
1060                 close(nullfd);
1061         }
1062 }
1063
1064 static struct thread *daemon_ctl_thread = NULL;
1065
1066 static int frr_daemon_ctl(struct thread *t)
1067 {
1068         char buf[1];
1069         ssize_t nr;
1070
1071         nr = recv(daemon_ctl_sock, buf, sizeof(buf), 0);
1072         if (nr < 0 && (errno == EINTR || errno == EAGAIN))
1073                 goto out;
1074         if (nr <= 0)
1075                 return 0;
1076
1077         switch (buf[0]) {
1078         case 'S': /* SIGTSTP */
1079                 vty_stdio_suspend();
1080                 if (send(daemon_ctl_sock, "s", 1, 0) < 0)
1081                         zlog_err("%s send(\"s\") error (SIGTSTP propagation)",
1082                                  (di && di->name ? di->name : ""));
1083                 break;
1084         case 'R': /* SIGTCNT [implicit] */
1085                 vty_stdio_resume();
1086                 break;
1087         case 'I': /* SIGINT */
1088                 di->daemon_mode = false;
1089                 raise(SIGINT);
1090                 break;
1091         case 'Q': /* SIGQUIT */
1092                 di->daemon_mode = true;
1093                 vty_stdio_close();
1094                 break;
1095         }
1096
1097 out:
1098         thread_add_read(master, frr_daemon_ctl, NULL, daemon_ctl_sock,
1099                         &daemon_ctl_thread);
1100         return 0;
1101 }
1102
1103 void frr_detach(void)
1104 {
1105         nodetach_daemon = false;
1106         frr_check_detach();
1107 }
1108
1109 void frr_run(struct thread_master *master)
1110 {
1111         char instanceinfo[64] = "";
1112
1113         frr_vty_serv();
1114
1115         if (di->instance)
1116                 snprintf(instanceinfo, sizeof(instanceinfo), "instance %u ",
1117                          di->instance);
1118
1119         zlog_notice("%s %s starting: %svty@%d%s", di->name, FRR_VERSION,
1120                     instanceinfo, di->vty_port, di->startinfo);
1121
1122         if (di->terminal) {
1123                 nodetach_term = true;
1124
1125                 vty_stdio(frr_terminal_close);
1126                 if (daemon_ctl_sock != -1) {
1127                         set_nonblocking(daemon_ctl_sock);
1128                         thread_add_read(master, frr_daemon_ctl, NULL,
1129                                         daemon_ctl_sock, &daemon_ctl_thread);
1130                 }
1131         } else if (di->daemon_mode) {
1132                 int nullfd = open("/dev/null", O_RDONLY | O_NOCTTY);
1133                 if (nullfd == -1) {
1134                         flog_err_sys(EC_LIB_SYSTEM_CALL,
1135                                      "%s: failed to open /dev/null: %s",
1136                                      __func__, safe_strerror(errno));
1137                 } else {
1138                         dup2(nullfd, 0);
1139                         dup2(nullfd, 1);
1140                         dup2(nullfd, 2);
1141                         close(nullfd);
1142                 }
1143
1144                 frr_check_detach();
1145         }
1146
1147         /* end fixed stderr startup logging */
1148         zlog_startup_end();
1149
1150         struct thread thread;
1151         while (thread_fetch(master, &thread))
1152                 thread_call(&thread);
1153 }
1154
1155 void frr_early_fini(void)
1156 {
1157         hook_call(frr_early_fini);
1158 }
1159
1160 void frr_fini(void)
1161 {
1162         FILE *fp;
1163         char filename[128];
1164         int have_leftovers;
1165
1166         hook_call(frr_fini);
1167
1168         vty_terminate();
1169         cmd_terminate();
1170         nb_terminate();
1171         yang_terminate();
1172 #ifdef HAVE_SQLITE3
1173         db_close();
1174 #endif
1175         log_ref_fini();
1176         frr_pthread_finish();
1177         zprivs_terminate(di->privs);
1178         /* signal_init -> nothing needed */
1179         thread_master_free(master);
1180         master = NULL;
1181         zlog_tls_buffer_fini();
1182         zlog_fini();
1183         /* frrmod_init -> nothing needed / hooks */
1184         rcu_shutdown();
1185
1186         if (!debug_memstats_at_exit)
1187                 return;
1188
1189         have_leftovers = log_memstats(stderr, di->name);
1190
1191         /* in case we decide at runtime that we want exit-memstats for
1192          * a daemon, but it has no stderr because it's daemonized
1193          * (only do this if we actually have something to print though)
1194          */
1195         if (!have_leftovers)
1196                 return;
1197
1198         snprintf(filename, sizeof(filename), "/tmp/frr-memstats-%s-%llu-%llu",
1199                  di->name, (unsigned long long)getpid(),
1200                  (unsigned long long)time(NULL));
1201
1202         fp = fopen(filename, "w");
1203         if (fp) {
1204                 log_memstats(fp, di->name);
1205                 fclose(fp);
1206         }
1207 }
1208
1209 #ifdef INTERP
1210 static const char interp[]
1211         __attribute__((section(".interp"), used)) = INTERP;
1212 #endif
1213 /*
1214  * executable entry point for libfrr.so
1215  *
1216  * note that libc initialization is skipped for this so the set of functions
1217  * that can be called is rather limited
1218  */
1219 extern void _libfrr_version(void)
1220         __attribute__((visibility("hidden"), noreturn));
1221 void _libfrr_version(void)
1222 {
1223         const char banner[] =
1224                 FRR_FULL_NAME " " FRR_VERSION ".\n"
1225                 FRR_COPYRIGHT GIT_INFO "\n"
1226                 "configured with:\n    " FRR_CONFIG_ARGS "\n";
1227         write(1, banner, sizeof(banner) - 1);
1228         _exit(0);
1229 }